Through the actions of bradykinin (BK) and angiotensin II (ANG II), the kallikrein-kinin and renin-angiotensin systems, respectively, regulate cardiovascular mechanisms in both mammals and fish. The myotropic and cardiovascular actions of homologous BK from the little skate, Leucoraja erinacea, were examined in the little skate. Administration of skate BK in vivo produced a biphasic increase in blood pressure and constricted the 1st branchial, mesenteric and celiac arteries in vitro. Co-administration of skate BK with several pharmacological agents suggest multiple pathways are involved in mediating the myoactivity of the BK in the little skate. The myotropic effects of ANG peptides were also assessed in the little skate and addition of homologous ANG II to pre-constricted vessels in vitro demonstrated a dose-dependent vasodilation. Morover, addition of skate BK in a heterologous bioassay produced a dose-dependent vasodilator effect in the aorta of the mouse suggesting conservation of this ancient peptide-receptor complex in mammals.

Angiotensin-converting enzyme 2 (ACE2) is an important component of the renin-angiotensin system (RAS). ACE2 is thought to have a renoprotective effect in diabetic nephropathy because it is capable of degrading profibrotic angiotensin II to potentially protective angiotensin-(1-7). Podocyte death and detachment is a key component of diabetic nephropathy. ACE2 is localized in the podocyte and during a diabetic state, podocyte ACE2 expression is reduced. The purpose of this study was to determine the effects of podocyte-specific ACE2 overexpression on the course of diabetic nephropathy. Diabetes was induced using streptozotocin in transgenic mice with podocyte-specific overexpression of human ACE2. The following parameters were assessed: systolic blood pressure, glomerular filtration rate, urinary albumin excretion, mesangial and glomerular area, and podocyte number. Transgenic diabetic mice showed a significant transient attenuated increase in albuminuria, an attenuated increase in mesangial area, decreased glomerular area, and preserved podocyte number, compared to wildtype diabetic mice. This was independent of a change in blood pressure. This study showed that the podocyte-specific overexpression of human ACE2 attenuates the development of diabetic nephropathy.

Through the actions of bradykinin (BK) and angiotensin II (ANG II), the kallikrein-kinin and renin-angiotensin systems, respectively, regulate cardiovascular mechanisms in both mammals and fish. The myotropic and cardiovascular actions of homologous BK from the little skate, Leucoraja erinacea, were examined in the little skate. Administration of skate BK in vivo produced a biphasic increase in blood pressure and constricted the 1st branchial, mesenteric and celiac arteries in vitro. Co-administration of skate BK with several pharmacological agents suggest multiple pathways are involved in mediating the myoactivity of the BK in the little skate. The myotropic effects of ANG peptides were also assessed in the little skate and addition of homologous ANG II to pre-constricted vessels in vitro demonstrated a dose-dependent vasodilation. Morover, addition of skate BK in a heterologous bioassay produced a dose-dependent vasodilator effect in the aorta of the mouse suggesting conservation of this ancient peptide-receptor complex in mammals.

v, 244 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 1981

v, 244 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physiology, 1981

Thesis (Ph.D.)--Michigan State University. Dept. of Pharmacology and Toxicology, 2008. / Title from PDF t.p. (viewed on Mar. 30, 2009) Includes bibliographical references (p.177-201). Also issued in print.

No description available.

The renin angiotensin aldosterone system is the dominant hormonal regulatory system controlling sodium balance and therefore blood pres- sure homeostasis. Abnormal modulation of this system is implicated in the pathogenesis of hypertension and end organ injury. We have previously developed the Cyp1a1-Ren2 transgenic rat to model an- giotensin II (ANG II) dependent hypertension. In this model hyper- tension causes renal injury, predominantly in the preglomerular vas- culature. The susceptibility to renal injury has a genetic component. A consomic/congenic study identified angiotensin converting enzyme (Ace) as an important modifer. However, renal injury is unlikely to be in uenced by a single gene. In this thesis it was hypothesised that examination of a renal microar- ray to compare the relative expression in F344 (susceptible) and Lewis (relatively protected) strains would reveal further genetic factors me- diating renal injury susceptibility. Genome wide expression analysis confirmed that Ace was a key modifier gene. Furthermore, the puriner- gic receptors P2x7 and P2x4 were identified as additional candidates. Gene and protein expression of these P2X receptors were both higher in F344 compared with Lewis. Immunohistochemistry localised P2X7 and P2X4 to the renal vasculature and tubules: the expression pattern was similar in both strains but became distinct in the renal medulla. F344, but not Lewis, responded to acute antagonism of P2X7 and P2X4. F344 showed a significant drop in blood pressure but maintained renal blood ow, indicative of tonic renal vasoconstriction. When ANG II was infused into F344 rats, there was a modest increase in blood pressure and an impairment of the pressure-natriuresis mecha- nism but no overt injury. Blood oxygenation-level dependent magnetic resonance imaging of the kidney identified a decrease in renal R2* sig- nal following P2X7 and P2X4 antagonism in ANG II infused F344 rats. P2X7/4 receptor activation reduces oxygenation and suppresses pressure-natriuresis. These effects are pro-biotic and may underpin susceptibility to renal injury.

Class of 2005 Abstract / Objective: The purpose of this study was to retrospectively determine if individuals within the SAVAHCS home-based patient population with a diagnosis of diabetes mellitus are receiving an angiotensin-converting-enzyme inhibitor (ACE-I) based on recent evidence supporting its use in these patients. Research Design: A retrospective, chart review of 41 patients with a diagnosis of diabetes mellitus from November 1, 2004 to December 31, 2005. Methodology: This was a retrospective, chart review of all patients within the SAVAHCS home-based population with an active diagnosis of diabetes mellitus. Once the patients were identified, their clinical profiles were extracted from the VISTA computer system. The patients had data regarding age, gender, diabetes type, diagnoses of heart disease and hypertension, type of ACE- Inhibitor prescribed, blood pressure, HgbA1c, and height and weight in order to calculate body mass index (BMI). The patients were classified as either having or not having ACE-Inhibitor therapy. Results: The total number of diabetic patients currently receiving an ACE-Inhibitor was 24 (58.5%). This was significantly lower than the value of 80% predetermined (p=0.0352). Thirty-one patients were also found to have a diagnosis of hypertension (75.6%), with 18 of these patients having a prescription for an ACE-Inhibitor (43.9%). Four patients (9.8%) who were not currently on an ACE- Inhibitor had a documented history of cough induced by the use of these drugs. Clinical Relationships: ACE-Inhibitors are drug agents used to treat hypertension. They have also been shown to be of significant clinical value in diabetic patients, in both renal protective effects as well as to reduce cardiovascular risk, the most common cause of morbidity and mortality in diabetic patients.

No description available.