A series of investigations were undertaken to determine whether physical or emotional stress, catecholamines or naloxone (B-endorphon blocker) would increase serum total cholesterol and LDL and HDL levels. Physical stress given daily over a period of time caused a steady increase in serum total cholesterol and LDL without a significantly altering high density lipoproteins (HDL) or serum triglycerides. Daily injections of epinerphrine in oil caused an increase in both serum total cholesterol and LDL levels while daily injections of norepinephrine did not. Reversal of the treatments caused a reversed response in both groups of rats. Similar increases in both total cholesterol and LDL levels occurred in graduate students during preparation for their comprehensive written or oral thesis/dissertation defense. Injection of eigher dichloroisoproterenol (M.W. = 248) or naloxone (M.W. = 346) in rats prior to stress inhibited the increase in total cholesterol and LDL levels, although naloxone at the dosage given was more effective, possibly due to its larger molecular weight. When naloxone plus epinephrine was injected into non-stressed rats, there was a significant increase in total cholesterol and LDL levels, but the increase was not as great as that of groups injected with epinephrine only. Stressed, adrenalectomized rats exhibited higher cholesterol and LDL levels than the normal reported range for rats of their age and weight, but their levels did not differ from those of stressed, sham-operated rats indicating that the adrenals per se are not needed for stress-induced elevation of blood LDL levels.

Fatal and non-fatal opioid overdoses resulting from opioid induced respiratory depression are a significant problem throughout the world. Whilst the opioid receptor antagonist, naloxone hydrochloride, can effectively reverse opioid overdoses, its use is limited because of the adverse effects it produces. These include severe withdrawal and the reversal of analgesia produced by opioid receptor agonists. In this project, the peripherally acting opioid receptor antagonist, naloxone methiodide, was investigated for its potential to reverse opioid induced respiratory depression without altering centrally mediated effects, such as withdrawal. In the publications presented in this thesis, naloxone hydrochloride and naloxone methiodide were shown to effectively reverse the decreases in respiratory rate produced by the administration of morphine, methadone and heroin in mice. Naloxone hydrochloride and naloxone methiodide also reversed the analgesia produced by these opioid receptor agonist treatments, but only naloxone hydrochloride induced significant withdrawal. The doses of naloxone methiodide required to produce the effects described above were higher than the naloxone hydrochloride doses required. Radioligand binding techniques indicated that this was due to a difference in the affinity of naloxone hydrochloride and naloxone methiodide for µ, δ and κ opioid receptor binding sites. Radioligand binding techniques were also used to confirm that naloxone methiodide, or its metabolites, could not readily cross the blood brain barrier. Therefore, the effects of naloxone methiodide appear to be mediated outside the central nervous system. The final publication aimed to extend our knowledge of opioid induced respiratory depression by utilising new radiotelemetry technology to test the efficacy of naloxone methiodide in rats subjected to a chronic opioid administration regime. This experiment showed that circadian rhythm plays a role in the development of tolerance to the cardiorespiratory effects of continuous and chronic methadone administration, and that naloxone hydrochloride and naloxone methiodide treatment can increase respiratory rate and heart rate after this methadone administration. Therefore, naloxone methiodide can effectively antagonise the peripheral effects produced by opioid receptor agonists. Peripherally acting opioid receptor antagonists should be developed in the future to prevent or treat the adverse effects of opioid receptor agonists. / Thesis (Ph.D.)--Department of Clinical and Experimental Pharmacology, 2004.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 108-129).

Aferentes nociceptivos primários se projetam da periferia para o corno posterior da medula espinhal onde ativam grande número de neurônios de segunda ordem e de projeção. Há evidências de que a passagem de informações nociceptivas pelo CPME seguindo para níveis rostrais do sistema nervoso central, sofre profundas influências excitatórias e inibitórias. A presente pesquisa teve como objetivo comparar os efeitos dos antagonistas de opióides (naloxona), de serotonina (metissergida) e de noradrenalina (fentolamina), administrados por via subaracnóidea, sobre as fases I, intermediária e II do teste da formalina modificado, em ratos. Para tanto, foram utilizados 35 ratos wistar machos, pesando entre 220 e 300 gramas, distribuídos aleatoriamente em cinco grupos (n = 7) para receber solução salina (GC), fentolamina (GF), naloxona (GN), metissergida (GM) ou fentolamina associada a metissergida (GFM). A indução da dor foi realizada com administração de solução de formalina na região dorsal da pata posterior direita. Todas as elevações da pata, não relacionadas à marcha foram consideradas e a contagem foi realizada continuamente durante o período de 60 minutos. O teste foi dividido em três fases; fase I, intermediária e fase II, sendo que a fase I compreendeu o número de elevações durante os primeiros 5 minutos, a fase intermediária do sexto ao vigésimo minuto e a fase II, do vigésimo primeiro ao sexagésimo minuto. A análise estatística dos resultados obtidos foi realizada utilizando o programa SPSS (Statistical Package for Social Sciences), adotando o nível de significância de 5%. Para as variáveis: peso, idade e fase I do teste, os grupos foram estatisticamente semelhantes. Nos cinco grupos estudados, a fase intermediária diferenciou-se das outras duas, enquanto que as fases I e II foram estatisticamente semelhantes. Para a variável fase intermediária foi encontrada uma diferença estatisticamente significante entre os grupos GF, GM e GFM quando comparados com os grupos GC e GN, e para a variável fase II foi encontrada diferença significante entre o grupo GN em comparação a todos os outros grupos. No presente estudo, a metissergida e a fentolamina se mostraram eficazes em inibir o efeito modulador espinhal da dor, sugerindo efeito noradrenérgico e serotoninérgico inibitório da transmissão nociceptiva espinhal, sem haver efeito somatório ou potencializador quando utilizados em associação. Entretanto, estes efeitos não foram observados com naloxona, e assim um efeito opióide modulador espinhal, na interfase do teste não ficou estabelecido. Durante a fase II, a naloxona causou redução da resposta nociceptiva à formalina, corroborando a hipótese de que exerça atividade sobre os receptores -opiáceos / Primary nociceptive afferents are projected from the periphery to the dorsal horn of the spinal cord, where they activate a large number of second-order and spinal projection neurons. There are evidences that the passage of nociceptive information through the posterior horn of the spinal cord towards rostral levels of the central nervous system (CNS) are under profound excitatory and inhibitory influences. This research had as objective to compare the effects of the naloxone, methysergide and phentolamine, administered by intrathecal route, under phases I, II and intermediary of the modified formalin test in rats. Therefore, 35 male Wistar rats between 220 and 300 grams, randomly distributed in five groups (n = 7) to receive saline solution (GS), phentolamine (GF), naloxone (GN), methysergide (GM) or phentolamine associated to methysergide (GFM) were used. The induction of pain was performed with administration of formalin solution in the dorsal region of the posterior right paw. All paw lifting, not related to the march, were taken into account and the count was continuously performed during the 60 minute period. The test was divided into three phases: phase I, intermediary and phase II, whereas phase I comprised the number of elevations during the first five minutes, the intermediary phase from the sixth to the twentieth minute, and phase II, the number of elevations from the twentieth first minute up to the sixtieth minute to the sixtieth minute. The statistical analysis of the results obtained was performed using the program SPSS (Statistical Package for Social Sciences), adopting a 5% significance level. For the variables: Weight, age and phase I of the test, the groups were statistically similar. In the five studied groups, the intermediary phase was different from the other two, while phases I and II were statistically similar. For the intermediary phase variable it was found a statistically significant difference among groups GF, GM, GFM when compared with groups GS and GN, and for the phase II variable it was found significant difference between group GN when compared with groups GC, GF, GM and GFM. In this study, methysergide, a non-selective antagonist of receptors 5-HT and phentolamine, a non-selective adrenoceptor antagonist, were effective in inhibiting the spinal pain modulating effect, suggesting inhibitory noradrenergic and serotonergic effect of spinal nociceptive transmission. However, such effects were not noticed with naloxone, and thus, a modulating spinal opioid effect was not established in the test interphase. During phase II of the formalin test, naloxone causes the decrease of nociceptive response to formalin, suggesting that the k-opiate receptors are involved in naloxone-induced analgesia.

Le tissu adipeux (TA) est connu pour sa plasticité puisqu'il est capable de s'hypertrophier ou de s'atrophier, en fonction de la situation métabolique de l'individu. Cette plasticité est liée au fait que le TA joue un double rôle dans le maintien de la balance énergétique : il est à la fois i) réserve d'énergie mobilisable (adipocytes blancs) mais également ii) consommateur d'énergie via la thermogénèse (adipocytes bruns, adipocytes beiges). En raison de l'évolution croissante des maladies métaboliques dites de surcharge dans lesquelles ce TA va s'hypertrophier, la majorité des études abordent cette notion de plasticité à l'échelle cellulaire, et se focalise ainsi sur les adipocytes (prolifération, différenciation, activité) et les autres populations cellulaires résidant dans le TA, capables d'interagir avec eux. En revanche, il y a très peu d'études sur cette plasticité à l'échelle tissulaire. Au cours de ma thèse, je me suis intéressée i) à l'organisation tissulaire d'un dépôt de TA blanc (dépôt sous-cutané inguinal) et ii) les conséquences d'une ablation massive du TA blanc. L'ensemble de ce travail a été réalisé chez la souris.A l'aide de l'imagerie 3D sur tissu entier, nous montrons que ce dépôt est hétérogène : il est composé d'une partie dans laquelle il est possible de segmenter des entités fonctionnelles (lobules ?), située au cœur du dépôt, et d'une partie non segmentable, située à la périphérie du dépôt. Cette hétérogénéité structurale est associée à une hétérogénéité fonctionnelle : les deux régions se distinguent en termes de morphologie adipocytaire et de pattern d'expression génique. De plus, seule la partie segmentable répond à la mise au froid des animaux par une up-régulation du niveau d'expression d'Ucp1 et d'autres gènes marqueurs du " brunissement ". Parallèlement à cela, nous montrons que selon la souche de souris (C57bl6 et MRL), la réponse du TA inguinal à une ablation partielle n'est pas la même : chez la souris MRL (rare mammifère capable de régénération), ce dépôt adipeux est capable de régénérer, ce qui n'est pas le cas chez la souris C57Bl/6. La régénération est inhibée chez la souris MRL par un traitement avec un agoniste des récepteurs aux opioïdes (tramadol) alors qu'elle peut être induite chez la souris C57Bl/6 par un antagoniste de ces récepteurs (naloxone). Cette régénération est dépendante d'une forte et intense production d'espèces actives de l'oxygène par les granulocytes. L'utilisation de souris invalidées pour le récepteur mu démontre l'implication de cette sous-famille de récepteurs. Enfin, cet effet des opioïdes est majoritairement le fait des cellules immunitaires, et plus particulièrement les granulocytes. Ces données mettent en exergue une nouvelle vision du TA blanc sous - cutané, qui ne doit pas être considéré comme un tissu inerte mais bel et bien comme un tissu hétérogène complexe (structurellement et fonctionnellement) pouvant être capable de régénération. / Adipose tissue (AT) is very plastic tissue. During metabolic disease, it would be overdeveloped or atrophy. It is due to the fact that AT is i) energy storage thanks to white adipocyte and ii) energy consumer thanks to brown or brite adipocyte. The cellular composition is very well studied (adipocytes activity, proliferation, differenciation, link between AT stromal cells / adipocytes) but the tissue organization of AT is not known. During my thesis work, we study the i) tissular organization of white AT and ii) AT response after massive removal of white AT. Mice are used for this work. In the first step, our 3 dimensional imaging of white AT shows that AT is heterogeneous tissue: AT has 2 components: segmentable area, in the AT core and non-segmentable area, in the AT periphery. This structural heterogeneity is correlated with functional heterogeneity because segementable area differs to non-segmentable area from adipocyte shape and pattern genic expression. Furthermore, only segmentable area can be respond to cold exposure by Ucp1 up-regulation and browning genes markers. In the second step, massive ablation of subcutaneous white AT is performed on two mice strains: C57Bl/6 and MRL (known to be able to regenerate). MRL mice inguinal AT regenerate, unlike inguinal AT of C57Bl/6 mice. The use of antagonist of opioid receptor (naloxone) treatment leads regeneration AT in C57Bl/6. In opposite, opioid receptor agonist (tramadol) treatment in MRL mice inhibits AT regeneration. AT regeneration is dependant of burst oxydatif production by granulocytes. The use of the receptor knock down mice highlights that is the only receptor is involved in AT regeneration. More precisely, opioids effects are mediated by receptor on granulocyte immune cells.

The mortality in drug related deaths has increased in many countries, calling it an epidemic. Overdose caused by opioids have contributed to the increasing drug related deaths. This study aims to examine and compile which methods and strategies have shown to reduce the mortality in drug related deaths. Using a systematic review and no limitation to countries a mix of methods and strategies was found. Some Ministries of Health department list them as important in reducing damages and risk behavior related to addiction. The repressive approach that was historically dominated has shown less successful. Individuals own strengths and access to treatments and strategies are momentous. It is also of great importance that governments and health care applies the listed methods and strategies. Blood diseases have decreased with needle exchange programs as a result of having implemented the method. Medications for addiction treatment are improving living conditions for people with opioid addiction. Still there are problems and difficulties with access to addiction treatment and harm reduction strategies. Stigma and the historical perception of drug use and addiction are some of the reasons for the inaccessibility and lack of harm reduction strategies.

Our previous report showed that the brain peptide Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2) blocks the inhibitory effect of morphine sulfate on E-rosette formation by human peripheral blood lymphocytes (PBL). In this study, additional in vitro effects of Tyr-MIF-1 on human PBL were studied. The percentages of positive cells for CD 2, a sheep erythrocyte receptor, CD 4 and CD 8 were unchanged after incubation of PBL with morphine or morphine plus Tyr-MIF-1. Tyr-MIF-1 was not mitogenic by itself. The addition of Tyr-MIF-1 did not increase the proliferative response of PBL to Con A, although morphine did. Tyr-MIF-1 did not activate PBL to produce IL 2 nor did it affect the production of IL 2 by Con A-stimulated PBL. The results suggest that Tyr-MIF-1 does not directly modulate CD 2, CD 4 and CD 8 expression, does not alter the proliferative response of PBL, and does not affect the production of IL 2.

1. Whole-cell patch recordings were made from antidromically identified sympathetic preganglionic neurons (SPN) of immature rat spinal cord slices. Bath application of nociceptin (0.1-1 μmol/L) suppressed excitatory postsynaptic potentials (EPSP) and hyperpolarized a population of SPN; these effects were naloxone (1 μmol/L) insensitive. 2. Nociceptin suppressed the amplitude of EPSP without causing a concomitant change in glutamate-induced depolarizations, suggesting a presynaptic inhibitory action. 3. Analysis of current-voltage relationships showed that nociceptin hyperpolarized SPN by increasing an inwardly rectifying K+ current. 4. Intrathecal injection of nociceptin (3, 10 and 30 nmol) to urethane-anaesthetized rats dose-dependently reduced the mean arterial pressure and heart rate; these effects were not prevented by prior intravenous injection of naloxone (1 mg/kg). 5. Results from our in vitro and in vivo experiments suggest that nociceptin suppresses spinal sympathetic outflow either by attenuating excitatory synaptic responses or hyperpolarizing SPN.

No description available.

Rapidly Dissolving Polymeric Microneedle Skin Patch of Naloxone for Opioid Overdose Treatment Tijani Akeemat1, Maria J. Peláez2, Prashant Dogra2,3, Ashana Puri1 1 Department of Pharmaceutical Sciences, Bill Gatton College of Pharmacy, East Tennessee State University, Johnson City, TN 37614. 2 Mathematics in Medicine Program, Houston Methodist Research Institute, Houston, TX 77030, USA 3 Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY 10065, USA Worldwide opioid abuse affects over 16 million people. A major cause of death in abusers is overdosing. Naloxone (NAL) is an opioid inhibitor that reverses its respiratory depressing effect. The use of this drug is limited mostly to invasive delivery: intravenous (IV), intramuscular (IM) and subcutaneous (SC) due to its significant hepatic clearance and poor oral bioavailability (2%). These routes are painful and worse still is the need for frequent injections for patient stabilization due to the short half-life of NAL. Non-invasive intranasal forms exist but this is fraught with a couple of limitations such as nasal damage and epistaxis. The need for alternatives without these limitations is thus evident. The feasibility of the use of metal microneedles (MNs) for the transdermal delivery of NAL was demonstrated in-vitro and through in-vitro in-vivo correlation modeling in our lab. The goal of the current study was to design a rapidly dissolving polymeric MN patch with delivery and pharmacokinetic (PK) properties comparable to that seen with the commercially available NAL products, eliminating their highlighted limitations. NAL loaded rapidly dissolving polyvinyl pyrrolidone-based MN arrays (500 µm, 100 needles) were fabricated by the mold casting technique. The permeation profile of fabricated MNs over a predetermined time were assessed via an in-vitro permeation set up using porcine ear skin. Samples were analyzed via HPLC. To improve on drug flux and amount permeated, the effect of increasing MN length and density (no. of needles/unit area) were assessed by fabricating MNs 300 µm longer and those with density double that of the initial array. Factors such as drug load and polymer strength influenced the needle fabrication. Compared to passive permeation, a reduced lag time of about 15 min was observed with a significant drug flux of 15.09 ± 7.68 g/cm2/h seen in the first 1 h (pin-vitro in-vivocorrelation we were able to predict an optimized design of the patch that can reproduce the clinical PK of NAL obtained with commercial devices. Increasing needle density and/or patch area was found to be of greater significance. Overall, drug flux seen over 1 h depicts the applicability of fabricated needles in opioid overdose emergencies with delivery properties comparable to that with IM and IN delivery.