published_or_final_version / abstract / Medicine / Master / Master of Philosophy

Coronary Artery Disease (CAD) is one of the most common cardiovascular disorder in adults. CAD often results in myocardial infarction or angina (Wilson, 2003:21). It is an accepted fact that the incidence of CAD has reached endemic proportions in South Africa (Venter, 1993:15). Coronary Artery Bypass Graft (CABG) surgery, Percutaneous Transluminal Coronary Angioplasty (PTCA) and insertion of a coronary stent are major therapeutic approaches to the treatment of CAD. However, these procedures do nothing to correct the underlying disease process (Hunt, Hendrata, Myles, 2000:389; Venter, 1993:15). Due to physiological changes patients suffering from CAD are expected to make lifestyle adaptations, in order to improve quality of life and prevent further damage to coronary arteries (Gotto, 1987:29). It is suspected that patients do not always adapt their lifestyle when they suffer from CAD, or if they do, do not maintain these adaptations. The following question emerges: • Do patients with coronary artery disease adapt their lifestyle and if they do, do they maintain these adaptations? The purpose of this study is to explore and describe the extent to which patients with CAD who underwent CABG, PTCA or insertion of a coronary stent adapt their lifestyles and to what extent they maintain these adaptations. Secondly, the purpose is to set guidelines to help with the improvement of lifestyle adaptations and contingency of adaptations. The objectives of the study is to explore and describe the extent to which patients with CAD adapt their lifestyles following CABG surgery, PTCA or insertion of a i coronary stent, the comparison of the extent of these lifestyle adaptations after two and four months and to set guidelines to improve the extent and contingency of lifestyle adaptations. An explorative and descriptive study was done in order to explore and describe the extent to which patients with CAD, who underwent CABG surgery, PTCA or insertion of coronary a stent, adapted their lifestyle, and to determine the maintenance of these lifestyle adaptations. For the purpose of this study questionnaires, based on a conceptual framework, were designed. The questionnaires enabled the researcher to explore and describe the lifestyle adaptations that patients with CAD underwent. The study was conducted in five private hospitals in Gauteng. The data obtained confirmed that patients suffering from CAD do adapt their lifestyle after having CABG surgery, PTCA or insertion of a coronary stent. Data also showed that the presence of a cardiac rehabilitation centre at the hospital where participants were treated, has a significant influence on patients’ ability to adapt their lifestyle and to maintain this new lifestyle. / Dr. W.O.J. Nel Ms. W. Jacobs

Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Introduction Cardiovascular disease is one of the leading causes of death in the world. Formation of harmful reactive oxygen species (ROS) is associated with several pathological conditions, and contributes to ischaemia/reperfusion injury. Antioxidants can be added to the diet in an attempt to decrease the prevalence of cardiovascular disease by decreasing the harmful effects of ischaemia/reperfusion injury. Red Palm Oil (RPO) consists of saturated, monounsaturated and polyunsaturated fatty acids and is rich in antioxidants such as -carotene, tocopherols and tocotrienols. It has previously been shown that RPO-supplementation improved reperfusion mechanical function. In these studies it was found that RPO might exert its beneficial effects during reperfusion through increased PKB/Akt pathway activity, which may lead to inhibition of apoptosis and improved mechanical function. Aims The aims of this study were: 1) to determine whether RPO-supplementation protected against ischaemia/reperfusion injury in the isolated perfused rat heart, 2) to confirm RPO-supplementation’s effect on the PKB/Akt pathway activity and, 3) to elucidate the regulators in the PKB/Akt pathway that RPOsupplementation influenced. Methods Male Wistar rats were divided into 4 groups, 2 control groups and 2 experimental groups. The 2 control groups were fed a standard rat chow (SRC) for 4 weeks. The two experimental groups received SRC and RPOsupplementation for 4 weeks. Hearts were excised and transferred to a Langendorff perfusion apparatus and perfused with Krebs-Henseleit buffer. Mechanical functional recovery was measured after 25 min of total global noflow ischaemia. The following parameters were also measured during various time points in the protocol: left ventricular develop pressure, heart rate, coronary flow, rate pressure product. Hearts were also freeze-clamped for biochemical analysis at 10 min during reperfusion. The biochemical analysis was aimed at determining PKB/Akt involvement. In a second protocol, hearts were subjected to the same perfusion protocol, but wortmannin was also added to the perfusion fluid, in order to inhibit PI3- kinase. Results Hearts from the RPO-supplemented rats showed an improved RPP recovery (92.26 ± 5.89 % vs 63.86 ± 7.74 %) after 10 min of reperfusion. This finding corroborated the findings of previous studies. Hearts of the RPOsupplemented rats perfused with wortmannin, showed increased RPP recoveries at several time points. Biochemical results showed that wortmannin did indeed inhibit PI3-K phosphorylation in the RPO-supplemented group, as was expected. The RPO-supplemented group that was perfused with wortmannin had an increased PKB/Akt (Ser473) phosphoyrylation, when compared to the wortmannin control group. It was also found that the combination of RPO and wortmannin had prosurvival effects. Discussion This study showed that RPO-supplementation offered protection against ischaemia/reperfusion injury in the Langendorff-perfusion apparatus at 10 min into reperfusion. Thereafter the significance of the protection was lost. This protection has been confirmed in several previous studies and several mechanisms have been proposed for this protection. Since no conclusive evidence exists on the precise mechanism of protection, our investigation focused on the regulators of the pro-survival PKB/Akt pathway. An improved functional recovery was also seen in the RPO-supplemented group that was perfused with wortmannin. This was an unexpected finding, because Wortmannin is a known PI3-kinase inhibitor (as was confirmed by our biochemical data). PI3-kinase phosphorylation leads to PKB/Akt phosphorylation and therefore, activation of a pro-survival pathway. It would be expected that wortmannin would inhibit PKB/Akt and thus decrease the survival of the cells. The RPO-supplementation thus reversed wortmannin’s detrimental effect to such an extent that the functional recovery was far better than RPO-supplementation alone. In the RPO + wortmannin group, PKB/Akt (Ser473) phosphorylation was increased, contrary to previous findings. This is an indication that RPO may have the ability to override wortmannin’s inhibitory effect on PI3-kinase, or that PKB/Akt (Ser473) may be phosphorylated independently of PI3-kinase. / AFRIKAANSE OPSOMMING: Inleiding Kardiovaskulêre siektes is een van die hoof oorsake van sterftes in die wêreld. Die vorming van skadelike reaktiewe suurstof spesies word geassosieer met verskeie patologiese kondisies en dra ook by tot isgemie/reperfusie skade. ‘n Moontlike manier om die voorkoms van isgemie/herperfusie skade asook kardiovaskulêre siektes te voorkom, is om antioksidante by die dieet te voeg. Rooi Palm Olie (RPO) bevat versadigde, mono-onversadigde en polionversadigde vetsure. RPO bevat ook ‘n oorvloed van antioksidante soos β- karoteen en tokoferole en tokotriënole. Dit is bewys in vorige studies dat RPO-aanvulling verbeter funksionele herstel. Hierdie voordelige effekte mag dalk wees agv verhoogde PKB/Akt pad aktiwiteit. Die PKB/Akt pad word geassosieer met die inhibisie van apoptose en verhoogde meganiese funksie. Doelwitte Die doelwitte van hierdie studie was om te bepaal of 1) RPO-aanvulling beskermende effekte teen isgemie/herperfusie skade in die geisoleerde rotharte het, 2) Bevestig of RPO-aanvulling wel die PKB/Akt pad beïnvloed 3). om die effekte wat RPO-aanvulling het op die reguleerders van die PKB/Akt pad te onthul. Metodes Manlike Wistar rotte is in 4 groepe verdeel. 2 Groepe kontrole rotte is ‘n standaard rotkosmengsel gevoer vir 4 weke. Die 2 eksperimentele groepe het ook ‘n standaard rotkosmengsel gekry plus ‘n RPO-aanvulling vir 4 weke. Harte is uitgesny en op ‘n Langendorff perfusie sisteem gemonteer en met Krebs-Henseleit buffer geperfuseer. Meganiese funksie herstel is gemeet na 25 min totale globale geen-vloei isgemie. Linker ventrikulêre ontwikkelde druk, harttempo, koronêre vloei en tempo druk produk is gemeet by verskillende tydpunte. Sommige harte is na 10 min herperfusie vir biochemiese analiese gevriesklamp. Die biochemiese analisiese was beoog om die PKB/Akt pad betrokkenheid te bepaal. ‘n Tweede stel harte is aan dieselfde perfusie protokol blootgestel, maar wortmannin (PI3-kinase inhibitor) is ook bygevoeg by die perfusie vloeistof. Resultate Die groep wat met RPO aangevul is, het na 10 min herperfusie, ‘n verbeterde tempo druk produk herstel getoon (92.26 ± 5.89 % vs 63.86 ± 7.74. Hierdie bevinding is ook met ander studies bevestig. ‘n Interessante bevinding was dat die groep wat met RPO aangevul is en met wortmannin geperfuseer is, ‘n verbeterde meganiese funksionele herstel getoon het. Biochemiese resultate het getoon dat wortmannin wel PI3-K fosforilering geinhibeer het. Die harte van die rotte in die groep wat aangevul is met RPO en daarna met wortmannin geperfuseer is, het ‘n toename in PKB/Akt (Ser473) fosforilering getoon, relatief tot die wortmannin geperfuseerde harte van die rotte in die kontrole groep. Hierdie groep (RPO-aanvulling en wortmannin perfusie) het beskermende effekte getoon. Bespreking Hierdie studie het getoon dat RPO-aanvulling beskerming gebied het teen isgemie/herperfusie skade in die Langendorff geperfuseerde rothart na 10 min herperfusie. Daarna is die beduidenheid van die beskerming verloor. Hierdie bevindings ondersteun die resultate van vorige studies. Verskeie moontlike meganismes is voorgestel vir die beskerming, maar die presiese meganisme is nog nie duidelik nie. In hierdie studie is daar gekyk na die reguleerders van die PKB/Akt pad. Geen vorige studies het al gefokus op RPO-aanvulling en sy effek op die reguleerders van die PKB/Akt pad nie. ‘n Onverwagte bevinding is dat harte van die rotte in die RPO + wortmannin groep ‘n verbeterde funksionele herstel getoon het. Wortmannin is ‘n PI3- kinase inhibitor. PI3-K fosforilering lei tot PKB/Akt fosforilering, wat tot sel beskerming lei. Dus, aangesien wortmannin PI3-K inhibeer, sou dit verwag word dat wortmannin sel beskerming sal verminder. Die RPO het egter die wortmannin se nadelige effekte tot so ‘n mate oorskrei dat die funksionele herstel baie beter was as die RPO-aanvulling alleen. Die verhoogde PKB/Akt (Ser473) fosforilering, wat gesien is in die RPO + wortmannin groep kan toegeskryf word aan RPO se vermoë om wortmannin se nadelige effekte te oorskrei. ‘n Moontlike verduideliking vir hierdie bevinding mag wees dat rooi palm olie PKB/Akt (Ser473) op ‘n PI3-K onafhanklike manier fosforileer.

[Truncated abstract] Background: This thesis examines pharmacotherapy use in the secondary prevention of coronary heart disease. It includes antiplatelet agents, beta-blockers, statins and ACE inhibitors, all shown in landmark clinical trials and meta-analyses to reduce the risk of cardiac events in patients with known coronary disease. Underuse of effective preventive therapies represents a lost opportunity to reduce mortality and morbidity. Overseas studies have shown significant underuse of effective therapies at the time of hospital discharge following an acute event and later in ambulatory care. Australian data on prescribing practices following an acute coronary event and, ongoing use in ambulatory care are sparse. Aims: The aim of this thesis was to quantify the prescription of known effective therapies at the time of hospital discharge following an acute coronary event and ongoing use in ambulatory care. A secondary aim was to identify barriers to optimal secondary prevention thus providing an evidential basis to recommend change. Methods: This was an observational study of a cohort of post-MI patients admitted to a tertiary and affiliate hospital in Perth, Western Australia. The continuum of care from the treatment plan at discharge through to the treatment regimen and risk factor management 12 months post-MI was examined. The intermediate step, communication about the treatment plan with the patient and the primary health care provider was also examined. The study involved a review of hospital medical records and follow-up questionnaires to patients and their general practitioners at 3 and 12 months post-MI. All post-myocardial patients were included in the analysis of prescriptions at discharge. The follow-up study included patients 80 years and younger with no terminal conditions. Patient interviews at 3 months and interviews and focus groups with key hospital staff provided qualitative data to inform the quantitative data.

Thesis (PhD)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: The reperfusion injury after myocardial ischemia is relevant in the clinical setting, after cardiopulmonary bypass for cardiac surgery, after PTCA and stenting and after cardiopulmonary resuscitation. The components of the reperfusion injury considered in this study were myocardial stunning and reperfusion arrhythmias. Calcium antagonists have been shown to be beneficial in attenuating the myocardial reperfusion injury in the in vitro and in vivo laboratory setting (Lamping, Gross 1985, Przyklenk and Kloner 1988, Taylor 1990, Ehring 1992, Gross and Piper 1992). However systemic administration of a dose of calcium antagonist, large enough to attenuate the myocardial reperfusion injury in the clinical setting, would inevitably lead to unwanted systemic side effects of the drug. The aim of this study was to investigate the hypothesis that an adequate dose of verapamil administered timeously, directly into the ischemic myocardium, would attenuate the reperfusion injury, either when administered from the onset of ischemia, or from 3 minutes before reperfusion. The anesthetized open chest porcine model of myocardial ischemia (15 min total LAD occlusion) and reperfusion was employed in this study. A low dose of verapamil (0.5 mg/8mt or 0.0625mg/mt), a high dose of verapamil (2mg/8m or O.25mg/ml), or vehicle (saline) (8ml) was infused over 8 minutes, directly into the LAD coronary artery supplying the ischemic segment. The infusion was started either at the onset of ischemia, or from 3 minutes before reperfusion. The time taken for the various parameters to return to pre ischemic values was compared between the different groups. The results showed that the high dose of verapamil (2mg) attenuated the reperfusion injury both when administered from the onset of ischemia, and when administered from 3 minutes before reperfusion, compared to either the low dose of verapamil, or the saline infusions. The high dose of verapamil groups had a faster recovery of both systolic contractile function and diastolic function and a lower incidence of ventricular fibrillation on reperfusion. There were no systemic effects of verapamil infusion in any of the groups. The clinical setting of cardiac surgery expressly lends itself to the clinical application of this finding. There is direct access to the coronary arteries both before ischemia and before reperfusion. A small dose of calcium channel blocking drug, with no systemic effect can be administered into the aortic root at the onset of ischemia, just prior to cardioplegia (when the heart is still warm), and after rewarming a few minutes prior to removal of the aortic cross clamp. / AFRIKAANSE OPSOMMING: Die reperfusie besering na miokardiale isgemie is klinies relevant na kardiopulmonêre omleiding vir hart chirurgie, na kardiologiese PTKA en stut prosedures en na kardiopulmonale ressussitasie. Die komponente van die reperfusie besering wat in hierdie studie oorweeg is, is miokardiale tydelike omkeerbare onderdrukking (stunning) en reperfusie arritmieë. Kalsium antagoniste is gewys om effektief te wees in beperking van die reperfusie besering in beide in vitro en in vivo laboratorium eksperimente (Lamping, Gross 1985, Przyklenk en Kloner 1988, Taylor 1990, Ehring 1992, Gross en Piper 1992). Sistemiese toediening van 'n dosis kalsium kanaal blokker, voldoende om die miokardiale reperfusie besering in die pasiënt te beperk, lei egter tot ongewenste sistemiese newe effekte van die middel. Die doel van die studie was om die hipotese te ondersoek dat 'n voldoende dosis verapamil, wat betyds direk toegedien is aan die isgemiese miokardium, die reperfusie besering sal beperk, ongeag of dit toegedien is vanaf die begin van isgemie, of van 3 minute voor reperfusie. Die vark model van miokardiale isgemie en reperfusie is aangewend in die studie. Die varke was tydens die eksperiment onder narkose, met die borskas oop, en 15 minute totale LAD okklusie is toegepas. 'n Lae dosis verapamil (0.5mg/8ml of 0.0625 mg/mt), of hoë dosis veraparnil (2mg/8mt of 0.25mg/mt), of saline (8mt) is oor 8 minute toegedien direk in die LAD arterie wat die isgemiese segment voorsien. Die infuus is begin direk na die aanvang van isgemie, of 3 minute voor die aanvang van reperfusie. Die tyd geneem vir terugvoer van parameters na pre isgemiese waardes is tussen die groepe vergelyk. Die resultate toon dat die hoë dosis veraparnil die reperfusie besering beperk in vergelyking met die lae dosis veraparnil of saline infusies, ongeag of dit van die begin van isgemie, of van 3 minute voor reperfusie toegedien word. Die groepe wat die hoë dosis veraparnil ontvang het, het vinniger herstel van sistoliese en diastoliese funksie getoon en het'n laer insidensie van reperfusie disritmieë, gewys. Geen sistemiese effekte van veraparnail infuus is waargeneem nie. Die kliniese toepassing van hierdie bevinding is by uitstek geskik vir toepassing tydens kardiopulmonale omleiding by kardiale chirurgie. Daar is direkte toegang tot koronêre arteries voor isgemie en voor reperfusie. 'n Klein dosis kalsium antagonis, met weglaatbare sistemiese effekte, kan toegedien word in die aorta wortel met die aanvang van isgemie, net voor kardioplegie toediening (hart steeds warm), en na verwarming, 'n paar minute voor verwydering van die aorta kruis klem.

心臟病目前仍然是最普遍的威脅人類生命安全的三大病因之一。同西藥相比, 傳統中醫藥具有多靶點，協同作用及小副作用等特性。在中藥歷史中， 丹參和葛根這兩種草藥經常出現在中藥方劑用於治療心血管相關的疾病，已有幾千年的歷史。 我們實驗室發現了一個丹參葛根湯劑具有保護動脈粥樣硬化病人心臟功能的作用，並且可以使收縮的大鼠大動脈舒張的作用。 本研究主要通過舒張豬冠狀動脈，提高大鼠對抗過氧化和離子擾動能力以及提高血管增生四個方面探討丹參葛根複方水提物 (質量比7:3) (DG配方)對血管的作用以提供其治療心血管疾病的藥理基礎。 / 在本研究的第一部， 我們主要探討了DG配方對缺血再灌注損傷的心臟及其心肌細胞的保護作用。我們發現DG配方明顯抑制了心臟損傷相關的肌酸激酶和乳酸脫氫的釋放。同時DG配方顯著促進了再灌注後冠狀動脈內血流量速度和收縮力度的恢復。這些結果說明DG配方可以保護缺血再灌注心臟並且有效促進其功能恢復。我們還觀察了長期給大鼠用DG配方14天後其心臟在缺血再灌注中的表現。類似於再灌注時給藥的結果，DG配方同樣抑制了損傷酶的釋放並且有效促進了冠狀動脈內血流量速度和收縮力度的恢復。 / 同時，在缺氧再灌注離體細胞模型中，我們發現DG配方明顯抑制了缺氧再灌注損傷帶來的細胞死亡。流式細胞儀分析結果表明，藥物處理組中的凋亡類的細胞明顯比對照組中少主要通過抑制促凋亡的caspase3表達明以及促進抗凋亡的Bcl2表達升高。DG配方減少了心肌細胞內細胞色素c從線粒體中釋放明顯以及抑制了線粒體去極化。這說明DG配方也保護了線粒體的膜的完整性，從而確保線粒體功能進而保證細胞的能量系統穩定。最有意思的是DG配方可以直接抑制缺氧再灌注相關的兩條通路, 它不僅抑制活性氧化物質的釋放, 同時也抑制了再灌注後鈣離子的累積。總之，DG配方以抗氧化和抗離子擾動的方式保護了在缺血缺氧再灌注損傷中心臟和心肌細胞的結構和功能。 / 第二部分的研究是關於DG配方對從豬心臟上分離的左冠狀動脈前室間支 (左前降支) 血管的作用及其內在的機制，我們的結果表明對由U46619引起的冠狀動脈血管收縮DG配方表現了濃度依賴的舒血管作用。而該作用並非依賴于內皮細胞及其釋放的舒張血管因數一氧化氮和前列腺素類似物環素和大部分的鉀離子通道。其中只有內向整合鉀離子通道部分參與了舒血管的過程。肌球蛋白輕鏈的磷酸化明顯被DG配方抑制，但是RhoA 的活性並沒有受其影響。鈣離子引發的血管收縮則被DG配方濃度依賴性的受到抑制。這部分的研究證明瞭DG配方主要通過類似鈣離子通道拮抗劑作用抑制鈣離子進入到血管平滑肌細胞減少肌球蛋白磷酸化達到舒張血管的作用。結果說明DG配方可以作為一種安全的藥物用於治療心血管疾病特別是高血壓和心絞痛。 / 本研究的第三部分是關於DG配方的促血管增生的作用。我們發現DG配方可以明顯促進斑馬魚的腸下動脈的出芽並且促進血管增生相關基因的表達，血管內皮細胞生長因數及其受體的mRNA表達。內皮細胞是血管增生的基礎。所以我們利用人源微血管內皮細胞檢測了DG配方在細胞的增生，遷移，分化和形成血管方面的影響以解釋它在斑馬魚中促進血管增生的作用機理。結果發現，DG配方明顯促進了該種內皮細胞的增殖，遷移和形成管狀結構。 / 綜上所述，DG配方可以通過舒張血管，抗氧化，抗離子紊亂和促進血管增生提供心血管保護功能。DG配方通過螯合活性氧化物質和抑制鈣離子的累積保護了因缺血再灌注引起的心臟損傷，說明DG配方可以作為手術的輔助藥物減少心臟病人在缺血再灌注過程中受到的損傷。它以拮抗L型鈣離子通道方式減少鈣離子進入到血管平滑肌細胞來舒張收縮的冠狀動脈血管。說明DG配方可以用於治療高血壓和心絞痛等心臟病。另外DG配方也可以促進血管增生，可用于心肌梗死病人促進其心臟血管系統重建，本研究對於未來臨床實驗具有重要的參考價值。 / Coronary heart diseases (CHD) are one of the most prevalent causes of premature death all over the world. In contrast to western medicine, traditional Chinese medicine (TCM) has shown the benefit of multi-targeting and synergism to treat CHD. Two kinds of Chinese herbs, Danshen (Radix Salviae Miltiorrhiza) (D) and Gegen (Radix Puerariae Lobatae) (G) always present on the TCM formula for treating heart disease. We found a useful formula of Danshen and Gegen decoction with weight ratio of 7:3 (DG) exerting properties of improving the heart function in patient with atheroslcerosis and providing vasodiation and antioxidant protection on the rat cardiovascular system. The present study was designed to evaluate the effects of DG on the vascular activity by its properties on antioxidant and anti-ion stunning to inhibiting the ischemia and reperfusion injury, vasodilation effect on pig coronary artery and angiogenesis effect on zebrafish model. / In the first part of the study, we explored protective effect of DG on rat hearts and cardiomyocytes after ischemia-reperfusion and hypoxia-reoxygenation injury. Comparing to control group, the release of creatine kinase (CK) and lactate dehydrogenase (LDH) significantly decreased in the DG treated groups in a dose-dependent manner. The recovery percentage of coronary flow and contractile force in the DG was higher than that in the control group. These results suggested that DG dose-dependently improved the heart function after ischemia and reperfusion injury in a dose-dependent manner. We also examined chronic effect of DG (14 days pretreatment) on rat heart with ischemia and reperfusion injury. DG induced rat heart with high potential to deal with I/R injury, less damaged enzymes release and high recovery percentage of heart function recovery. / In the cell hypoxia and reoxygenation model, DG significantly inhibited the cell death after H/R treatment with bcl2 expression increase and caspase3 expression decrease. DG also reversed the H/R-induced mitochondrial depolarization and inhibited cytochrome c diffusing out of mitochondria, which confirmed DG anti-apoptosis activity. DG also was found to significantly decrease the intracellular calcium accumulation and reactive oxygen species release within H9c2. / In the second part of present study, results revealed that DG elicited a concentration-dependent relaxation of U46619-preconstricted porcine coronary artery. DG-induced relaxation responses were not altered by the presence of endothelium-related dilator inhibitors, most potassium channel blockers, GMP and AMP pathway inhibitors and endothelium removal. Ba²⁺ (an inward rectifier K⁺ channel blocker) slightly attenuated DG-induced relaxation. The protein expression of phosphorylated myosin light chain (MLC) was inhibited by DG in a concentration-dependent manner whereas the activity of RhoA was not modified. Ca²⁺-induced contraction of coronary artery was inhibited by DG in a concentration-dependent fashion. DG acted as an antagonist of calcium channel inducing the porcine artery dilation. / The third part of the present study is about the pro-angiogenic effect of DG. We found that DG dose-dependently induced zebrafish sub-intestinal vessel sprouting and increased the mRNA expression of vascular endothelial growth factor (VEGF) and its receptors. To explore the underlying mechanism, we also examined the proangiogenic effect of DG on the angiogenesis of endothelial cells. The results showed that DG induced the HMEC-1 proliferation, migration and forming tube. / In conclusion, we found that DG could provide cardiac and cardiovascular protection by its multiple targets. It prevented heart injuries after ischemia or hypoxia and reperfusion through scavenging ROS and inhibiting calcium accumulation. Moreover, it mainly acts as an antagonist of L-type calcium channel to relax the contracted LAD vessel. It also exerted property of inducing angiogenesis in vivo and in vitro. Therefore, DG would be useful for treating coronary artery disease depending on its multiple targets. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Hu, Fan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 170-215). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Chapter 1 --- Intorduction --- p.1 / Chapter 1.1 --- Cardiovascular system and coronary artery diseases --- p.1 / Chapter 1.1.1 --- The cardiovascular system --- p.1 / Chapter 1.1.2 --- Contraction and relaxation of the vascular myocyte in arteries --- p.4 / Chapter 1.1.2.1 --- Ultrastructure of the vascular myocyte --- p.4 / Chapter 1.1.2.2 --- Contraction mechanisms of vascular myocyte --- p.5 / Chapter 1.1.2.3 --- Relaxation mechanisms of vascular myocyte --- p.7 / Chapter 1.1.3 --- Chronic coronary heart disease --- p.9 / Chapter 1.2 --- The way to treat chronic CAD --- p.11 / Chapter 1.2.1 --- Angiogenesis --- p.11 / Chapter 1.2.2 --- Clinical surgery for treating CAD --- p.13 / Chapter 1.2.2.1 --- Three common surgeries for treating CAD --- p.13 / Chapter 1.2.2.2 --- Ischemia and reperfusion (I/R) injury in surgeries --- p.15 / Chapter 1.2.3 --- Drugs for treating CAD --- p.19 / Chapter 1.2.3.1 --- Western medicine therapy in CAD --- p.19 / Chapter 1.2.3.2 --- Traditional Chinese Medicine treatment in CAD --- p.20 / Chapter 1.3 --- Aims of studies --- p.28 / Chapter 2 --- Materials and Methods --- p.29 / Chapter 2.1 --- Solutions and Materials --- p.29 / Chapter 2.1.1 --- Solutions --- p.29 / Chapter 2.1.2 --- Chemicals and enzymes --- p.36 / Chapter 2.2 --- Methods --- p.38 / Chapter 2.2.1 --- Herbal preparation --- p.38 / Chapter 2.2.2 --- Identification and quantification of chemical markers in Danshen and Gegen decoction (DG) --- p.38 / Chapter 2.2.3 --- Assay development for the determination of the DG marker compounds in rat plasma --- p.40 / Chapter 2.2.4 --- Isolation of pig left anterior descending coronary artery --- p.44 / Chapter 2.2.5 --- Isometric tension measurement --- p.45 / Chapter 2.2.6 --- Langendorff related experiment --- p.50 / Chapter 2.2.7 --- Cell culture of H9c2 cells --- p.54 / Chapter 2.2.8 --- Cell viability assay (MTT assay) --- p.56 / Chapter 2.2.9 --- Cell proliferation measurement --- p.57 / Chapter 2.2.10 --- Hypoxia and reperfusion cell model (H9c2) --- p.58 / Chapter 2.2.11 --- Determination of cell apoptosis with Annexin VFITC and PI double staining --- p.59 / Chapter 2.2.12 --- Measurement of mitochondria depolarization --- p.61 / Chapter 2.2.13 --- Measurement of ROS release --- p.63 / Chapter 2.2.14 --- Measurement of calcium localization in H9c2 cells by fluo4 dye and confocal microscopy --- p.64 / Chapter 2.2.15 --- Extraction of proteins from tissue, cell and subcellular fractions --- p.65 / Chapter 2.2.16 --- Western blot assay --- p.67 / Chapter 2.2.17 --- Human microvascular endothelial cells (HMEC1) cell culture --- p.68 / Chapter 2.2.18 --- Cell cycle analysis by PI staining --- p.69 / Chapter 2.2.19 --- Scratch assay for HMEC1cells migration --- p.70 / Chapter 2.2.20 --- Tube formation assay --- p.71 / Chapter 2.2.21 --- Vessel sprouting of Zebrafish --- p.72 / Chapter 2.2.22 --- Real time PCR --- p.74 / Chapter 2.2.23 --- Statistical analysis --- p.76 / Chapter 3 --- Chapter 3 Cardiac protection of Danshen and Gegen decoction in hypoxia/ischemia and reperfusion induced injury --- p.77 / Chapter 3.1 --- Introduction --- p.77 / Chapter 3.2 --- Results --- p.81 / Chapter 3.2.1 --- Cytotoxicity of DG --- p.81 / Chapter 3.2.2 --- The morphology alteration of H9c2 after H/R treatment --- p.83 / Chapter 3.2.3 --- Effect on H H9c2 cell survival after H/R treatment --- p.84 / Chapter 3.2.4 --- Effect on membrane skeleton of H9c2 cells with H/R injury --- p.86 / Chapter 3.2.5 --- Effect on the apoptosis in H9c2 cells induced by H/R injury --- p.88 / Chapter 3.2.6 --- Effect on cytochrome c release from mitochondria of damaged H9c2 cells --- p.92 / Chapter 3.2.7 --- Effect on mitochondria depolarization of H9c2 after H/R treatment --- p.94 / Chapter 3.2.8 --- Effect on reactive oxidant species (ROS) release --- p.96 / Chapter 3.2.9 --- Effect on calcium accumulation within H9c2 in the reperfusion phase --- p.98 / Chapter 3.2.10 --- Effect on heart functions of rat hearts with I/R injury (acute effect) --- p.101 / Chapter 3.2.11 --- Effect on heart function in rats with I/R injury (chronic effect) --- p.107 / Chapter 3.3 --- Discussion --- p.113 / Chapter 4 --- Chapter 4 Vasodilation effects of Danshen and Gegen decoction in porcine coronary artery and its underlying mechanism --- p.118 / Chapter 4.1 --- Introduction --- p.118 / Chapter 4.2 --- Results --- p.121 / Chapter 4.2.1 --- Investigations of endothelium dependent and independent mechanisms --- p.121 / Chapter 4.2.2 --- Effects on cAMP and cGMP pathway --- p.121 / Chapter 4.2.3 --- Effects on potassium channel opening --- p.121 / Chapter 4.2.4 --- Effects on calcium induced contraction and calcium sensitization --- p.122 / Chapter 4.2.5 --- Effects on MLC phosphorylations --- p.123 / Chapter 4.3 --- Discussion --- p.132 / Chapter 5 --- Chapter 5 In vitro and in vivo angiogenic effects of DG --- p.138 / Chapter 5.1 --- Introduction --- p.138 / Chapter 5.2 --- Results --- p.140 / Chapter 5.2.1 --- Effect on subintestinal vessels sprouting in the zebrafish embryo --- p.140 / Chapter 5.2.2 --- Effect on the transcription and expression of VEGFA and VEGF receptors -- Flt1 and KDR/Flk2 --- p.143 / Chapter 5.2.3 --- Effect on HMEC1 proliferation --- p.145 / Chapter 5.2.4 --- Effect on cell cycle of HMEC1 --- p.148 / Chapter 5.2.5 --- Effect on cell migration of HMEC1 --- p.151 / Chapter 5.2.6 --- Effect on tube formation of HMEC1 --- p.154 / Chapter 5.3 --- Discussion --- p.157 / Chapter 6 --- Chapter 6 Conclusions and future work --- p.160 / Chapter 6.1 --- Cardiac protection of DG in the I/R and H/R injury --- p.160 / Chapter 6.2 --- Vasodilation effect of DG on the porcine coronary artery --- p.165 / Chapter 6.3 --- Angiogenic effect of DG in vivo and in vitro --- p.167 / Chapter 6.4 --- Overall conclusion of the study --- p.169 / Chapter 7 --- References --- p.170

Yam Wing Sze. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 154-160). / Abstracts in English and Chinese. / Abstract English --- p.i / Chinese --- p.iii / Acknowledgments --- p.v / Table of contents --- p.vii / List of Tables --- p.x / List of Figures --- p.xi / List of Abbreviations --- p.xvi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Chinese Medicine and Western Medication --- p.1 / Chapter 1.2 --- Chinese Medicine and Compound Formula --- p.2 / Chapter 1.3 --- Cardiovascular disease (CVD) and atherosclerosis --- p.6 / Chapter 1.4 --- General Research Objectives --- p.19 / Chapter Chapter 2 --- Establishment of compound formulation and Extract Preparation --- p.21 / Chapter 2.1 --- Formulation searched from Chinese Pharmacopoeia --- p.21 / Chapter 2.2 --- Aqueous extract preparation --- p.25 / Chapter 2.2.1 --- Materials and Methods --- p.25 / Chapter 2.2.2 --- Discussion --- p.27 / Chapter Chapter 3 --- Vasodilation study --- p.28 / Chapter 3.1 --- Vascular Smooth Muscle Contraction and Relaxation --- p.28 / Chapter 3.2 --- Endothelium and Vasodilation --- p.30 / Chapter 3.3 --- Vasodilation in organ bath --- p.32 / Chapter 3.3.1 --- Materials and Methods --- p.32 / Chapter 3.3.2 --- Results --- p.35 / Chapter 3.3.3 --- Discussion --- p.40 / Chapter 3.4 --- Endothelium dependent vasodilation --- p.40 / Chapter 3.4.1 --- Materials and Methods --- p.43 / Chapter 3.4.2 --- Results --- p.45 / Chapter 3.4.3 --- Discussion --- p.54 / Chapter 3.5 --- Adrenoceptor and vasodilation --- p.55 / Chapter 3.5.1 --- Materials and Methods --- p.57 / Chapter 3.5.2 --- Results --- p.58 / Chapter 3.5.3 --- Discussion --- p.62 / Chapter 3.6 --- Potassium Channels and Vasodilation --- p.63 / Chapter 3.6.1 --- Materials and Methods --- p.65 / Chapter 3.6.2 --- Results --- p.67 / Chapter 3.6.3 --- Discussion and Summary --- p.77 / Chapter 3.7 --- Potential active components from Fenge and Danshen --- p.82 / Chapter 3.7.1 --- Materials and Methods --- p.82 / Chapter 3.7.2 --- Results --- p.83 / Chapter 3.7.3 --- Discussion --- p.87 / Chapter Chapter 4 --- Comparison of Fenge and Yege --- p.88 / Chapter 4.1 --- Vasodilative effects of Fenge and Yege --- p.89 / Chapter 4.1.1 --- Materials and Methods --- p.89 / Chapter 4.1.2 --- Results --- p.89 / Chapter 4.1.3 --- Discussion --- p.101 / Chapter 4.2 --- The comparison of antioxidative effect between Yege and Fenge --- p.104 / Chapter 4.2.1 --- Red blood cell hemolysis model --- p.106 / Chapter 4.2.1.1 --- Materials and Methods --- p.106 / Chapter 4.2.1.2 --- Results --- p.108 / Chapter 4.2.1.3 --- Discussion --- p.110 / Chapter 4.2.2 --- Ischemia-reperfusion on Langendroff --- p.112 / Chapter 4.2.2.1 --- Materials and Methods --- p.114 / Chapter 4.2.2.2 --- Results --- p.117 / Chapter 4.2.2.3 --- Discussion --- p.125 / Chapter Chapter 5 --- Comparison of Chemical Profiles of Fenge and Yege --- p.127 / Chapter 5.1 --- The application of HPLC --- p.127 / Chapter 5.2 --- HPLC standardization --- p.129 / Chapter 5.2.1 --- Materials and Methods --- p.132 / Chapter 5.2.2 --- Results --- p.133 / Chapter 5.2.3 --- Discussion --- p.144 / Chapter Chapter 6 --- "Summaries, Discussion and prospects" --- p.146 / Chapter 6.1 --- Summaries and Discussion --- p.146 / Chapter 6.2 --- Prospects --- p.148 / Chapter 6.2.1 --- "Cardiovascular tonic effect of pure compounds, extracts with difference solvents and their vasodilative mechanism." --- p.148 / Chapter 6.2.2 --- Macrophage Foam Cell and Atherosclerosis --- p.149 / Chapter 6.2.3 --- The D:F (7:3) and D:Y (7:3) compound formulae capsule with GMP --- p.152 / References --- p.154

3-Hydroxy-3-Methylglutaryl Coenzyme A (HMG CoA) reductase is a 97 kDa glycoprotein located in the endoplasmic reticulum responsible for cholesterol biosynthesis in mammalian liver and intestine. HMG CoA reductase inhibitors (statins) (e.g. simvastatin, mevastatin and parvastatin) are used clinically to treat and prevent coronary artery diseases by reducing plasma LDL-cholesterol level. Recent studies have demonstrated that statins can provide beneficial effects (pleiotropic effects) beyond its lipid-lowering activity. However, the modulatory effects of statins on ion channels activities have not been fully explored. Hence, this study is designed to demonstrate the existence of the HMG CoA reductase in various human isolate cardiovascular preparations and the modulatory effect(s) of simvastatin on both large-conductance calcium-activated (BKCa) and ATP-sensitive (IKATP) potassium channels of porcine isolated coronary vascular smooth muscle cells. / In conclusion, our results demonstrated the biochemical existence of HMG CoA reductase in various human isolated cardiovascular preparations and porcine isolated coronary artery. Simvastatin modulates the BKCa and IKATP channels of the porcine isolated coronary artery via different and multiple cellular mechanisms. / In this study, we demonstrated the biochemical existence of the HMG CoA reductase in various human isolated cardiovascular preparations and porcine isolated coronary artery. In addition, we demonstrated that simvastatin modulates both the BKCa channels and IKATP channels of porcine isolated coronary artery via different mechanisms. Acute application of simvastatin (100 nM) slightly enhanced whereas simvastatin (≥ 1 muM) inhibited the BKCa amplitude of porcine coronary artery smooth muscle cells. The classical HMG CoA reductase-mevalonate cascade is important in mediating the inhibitory effect of simvastatin observed at low concentrations (1 and 3 muM), whereas an increased PKC-delta protein expression and activation is important in simvastatin (10 muM)-mediated inhibition of BKCa channels. In contrast, the basal activity of the IKATP channels was not affected by simvastatin (1, 3 and 10 muM). However, acute application of simvastatin (1, 3 and 10 muM) inhibited the opening of the IKATP channels by cromakalim and pinacidil in a PP2A-dependent manner (sensitive to okadaic acid, a PP2A inhibitor). The okadaic acid-sensitive, simvastatin-mediated inhibitory effect on IKATP channel is mediated by an activation of AMPK in a Ca2+-dependent manner. Activation of AMPK probably increased the activity of the Na+/K+ ATPase and subsequently caused an influx of glucose via the SGLT1 down the Na + concentration gradient for the ouabain-sensitive, glucose-dependent activation of PP2A. / Seto, Sai Wang. / Adviser: Yiu-Wa Kwan. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3456. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 221-254). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

[Truncated abstract] The main objective of this study was to develop and validate a demographic/epidemiologic Markov model for population modelling/forecasting of CARPs as well as CHD deaths and incidence in Western Australia using population, linked hospital morbidity and mortality data for WA over the period 1980 to 2000. A key feature of the model was the ability to count events as individuals moved from one state to another and an important aspect of model development and implementation was the method for estimation of model transition probabilities from available population data. The model was validated through comparison of model predictions with actual event numbers and through demonstration of its use in producing forecasts under standard extrapolation methods for transition probabilities as well as improving the forecasts by taking into account various possible changes to the management of CHD via surgical treatment changes. The final major objective was to demonstrate the use of model for performing sensitivity analysis of some scenarios. In particular, to explore the possible impact on future numbers of CARPs due to improvements in surgical procedures, particularly the introduction of drug eluting stents, and to explore the possible impact of change in trend of CHD incidence as might be caused by the obesity epidemic. ... When the effectiveness of PCI due to introduction of DES was increased by reducing Pr(CABG given PCI) and Pr(a repeat PCI), there was a small decline in the requirements for PCIs and the effect seemed to have a lag. Finally, in addition to these changes when other changes were incorporated which captured that a PCI was used more than a CABG due to a change in health policy after the introduction of DES, there was a small increase in the requirements for PCIs with a lag in the effect. Four incidence scenarios were developed for assessing the effect of change in secular trends of CHD incidence as might be caused by the obesity epidemic in such a way that they gradually represented an increasing effect of obesity epidemic (assuming that other risk factors changed favourably) on CHD incidence. The strategy adopted for developing the scenarios was that based on past trends the most dominant component of CHD incidence was first gradually altered and finally the remaining components were altered. iv The results showed that if the most dominant component of CHD incidence, eg, Pr(CHD - no history of CHD) levelled off and the trends in all other transition probabilities continued into future, then the projected numbers of CABGs and PCIs for 2001-2005 were insensitive to these changes. Even increasing this probability by as much as 20 percent did not alter the results much. These results implied that the short-term effect on projected numbers of CARPs caused by an increase in the most dominant component of CHD incidence, possibly due to an ?obesity epidemic, is small. In the final incidence scenario, two of the remaining CHD incidence components-Pr(CABG - no history of CHD) and Pr(CHD death - no CHD and no history of CHD) were projected to level off over 2001-2005 because these probabilities were declining over the baseline period of 1998-2000. The projected numbers of CABGs were more sensitive (compared to the previous scenarios) to these changes but PCIs were not.

Tam Wing Yin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 82-100). / Abstracts in English and Chinese. / English abstrac --- p.I / 中文摘要 --- p.VI / Glossary --- p.X / Chapter Chapter 1. --- Background: / Chapter 1.1. --- Coronary heart disease in Hong Kong --- p.1 / Chapter 1.2. --- Coronary heart disease and atherosclerosis --- p.2 / Chapter 1.3. --- Pathogenesis of atherosclerosis --- p.2 / Chapter 1.4. --- Risk factors for atherosclerosis --- p.5 / Chapter 1.5. --- Homocysteine --- p.6 / Chapter 1.6. --- Folate --- p.10 / Chapter 1.7. --- Vitamin B12 --- p.13 / Chapter 1.8. --- Adhesion Molecules --- p.14 / Chapter 1.9. --- Phytoestrogen --- p.17 / Chapter 1.10. --- Secondary prevention of coronary artery disease --- p.20 / Chapter Chapter 2. --- "Heart disease, Danshen and Gegen in Chinese medicine" / Chapter 2.1. --- The record of Cardiac symptoms in Chinese Medicine --- p.24 / Chapter 2.2. --- Danshen (Salvia Miltriorrhiza) --- p.25 / Chapter 2.3. --- Gegen (Radix Pueraria) --- p.28 / Chapter Chapter 3. --- Surrogate atherosclerotic markers / Chapter 3.1. --- Flow-mediated dilatation of brachial artery (FMD) --- p.31 / Chapter 3.2. --- Carotid intima media thickness (IMT) --- p.32 / Chapter Chapter 4. --- Method / Chapter 4.1. --- Rational of the study --- p.33 / Chapter 4.2. --- Clinical protocol --- p.35 / Chapter 4.3. --- Measurement of plasma homocysteine --- p.38 / Chapter 4.4. --- Measurement of folate and vitamin B12 --- p.40 / Chapter 4.5. --- Measurement of soluble cellular adhesion molecules (CAMs) --- p.41 / Chapter 4.6. --- Measurement of plasma enterolactone --- p.43 / Chapter 4.7. --- Measurement of plasma hs-C-reactive protein --- p.44 / Chapter 4.8. --- Other laboratory tests --- p.45 / Chapter 4.9. --- High resolution ultrasound imaging --- p.46 / Chapter 4.10. --- Statistical analysis --- p.49 / Chapter 4.11. --- My contribution to this joint project --- p.49 / Chapter Chapter 5. --- Results / Chapter 5.1. --- Recruitment and outcomes of subjects --- p.51 / Chapter 5.2. --- Baseline characteristics --- p.53 / Chapter 5.3. --- Medical history and treatment received in the study subjects --- p.54 / Chapter 5.4. --- Safety profiles --- p.55 / Chapter 5.5. --- Severe adverse events --- p.56 / Chapter 5.6. --- Lipid profiles --- p.57 / Chapter 5.7. --- Secondary endpoints --- p.58 / Chapter 5.8. --- Primary endopoints --- p.59 / Chapter 5.9. --- The effect of statin usage on the primary endpoints / Chapter 5.10. --- The major determinant of the change in FMD by multivariate logistic regression / Chapter 5.11. --- Progress of lipid profiles and primary endpoints in the open label phase / Chapter Chapter 6. --- Discussion / Chapter 6.1. --- Brachial FMD --- p.66 / Chapter 6.2. --- Carotid IMT --- p.69 / Chapter 6.3. --- Brachial GTN --- p.70 / Chapter 6.4. --- Lipid-lowering effect --- p.72 / Chapter 6.5. --- Phytoestrogen --- p.72 / Chapter 6.6. --- Folate --- p.73 / Chapter 6.7. --- Vitamin B12 and glucose --- p.76 / Chapter 6.8. --- Summary of possible anti-atherogenic mechanism of D&G --- p.76 / Chapter 6.9. --- Placebo effect --- p.77 / Chapter 6.10. --- Safety profile --- p.77 / Chapter 6.11. --- Limitation of the study and suggestion of solution --- p.77 / Chapter 6.12. --- Suggestions and ummary of the future work --- p.79 / Chapter Chapter 7. --- Conclusions --- p.81 / References --- p.82