Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 9

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  apelin
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Apelin interacts with the APJ receptor to enhance inotropy. In heart failure, apelin-APJ coupling may provide a means of enhancing myocardial function. The alterations in apelin and APJ receptor concentrations with ischemic cardiomyopathy are poorly understood. We investigated the compensatory changes in endogenous apelin and APJ levels in the setting of ischemic cardiomyopathy. Male, Lewis rats underwent LAD ligation and progressed into heart failure over 6 weeks. Corresponding animals underwent sham thoracotomy as control. Six weeks after initial surgery, the animals underwent hemodynamic functional analysis in the presence of exogenous apelin-13 infusion and the hearts were explanted for western blot and enzyme immunoassay analysis. Western blot analysis of myocardial APJ concentration demonstrated increased APJ receptor protein levels with heart failure (1890750±133500 vs. 901600±143120 intensity units, n=8, p=0.00001). Total apelin protein levels increased with ischemic heart failure as demonstrated by enzyme immunoassay (12.0±4.6 vs. 1.0±1.2 ng/ml, n=5, p=0.006) and western blot (1579400±477733 vs. 943000±157600 intensity units, n=10, p=0.008). Infusion of apelin-13 significantly enhanced myocardial function in sham and failing hearts. We conclude that total myocardial apelin and APJ receptor levels increase in compensation for ischemic cardiomyopathy
In spite of significant progress in pharmacotherapy the incidence of newly diagnosed cases of cardiovascular diseases and cardiovascular morbidity is alarmingly high. Treatment of hypertension or heart failure still remains a serious challenge. Continuous attempts are made to identify the mechanisms that decide about susceptibility to pathogenic factors, and to determine effectiveness of a specific therapeutic approach. Coincidence of cardiovascular diseases with metabolic disorders and obesity has initiated intensive research for their common background. In the recent years increasing attention has been drawn to disproportionately greater number of depressive disorders and susceptibility to stress in patients with coronary artery disease. An opposite relationship, i.e. a greater number of sudden cardiovascular complications in patients with depression, has been also postulated. Progress in functional neuroanatomy and neurochemistry provided new information about the neural network responsible for regulation of cardiovascular functions, metabolism and emotionality in health and under pathological conditions. In this review we will focus on the role of neuromodulators and neurotransmitters engaged in regulation of the cardiovascular system, neuroendocrine and metabolic functions in health and in pathogenesis of cardiovascular diseases and obesity. Among them are classical neurotransmitters (epinephrine and norepinephrine, serotonin, GABA), classical (CRH, vasopressin, neuropeptide Y) and newly discovered (orexins, apelin, leptin IL-1ßeta, TNF-alpha, ghrelin) neuropeptides, gasotransmitters, eicozanoids, endocannabinoids, and some other compounds involved in regulation of neuroendocrine, sympatho-adrenal and parasympathetic nervous systems. Special attention is drawn to those factors which play a role in immunology and inflammatory processes. Interaction between various neurotransmitter/neuromodulatory systems which may be involved in integration of metabolic and cardiovascular functions is analyzed. The survey gives evidence for significant disturbances in release or action of the same mediators in hypertension heart failure, obesity, diabetes mellitus, metabolic syndrome, starvation, chronic stress, depression and other psychiatric disorders. With regard to the pathogenic background of the cardiovascular diseases especially valuable are the studies showing inappropriate function of angiotensin peptides, vasopressin, CRH, apelin, cytokines and orexins in chronic stress, cardiovascular and metabolic diseases. The studies surveyed in this review suggest that multiple brain mechanisms interact together sharing the same neural circuits responsible for adjustment of function of the cardiovascular system and metabolism to current needs.
9
Content available remote

Role of feed-regulating peptides on pancreatic exocrine secretion

67%
In recent two decades a group of feed intake-regulating peptides (i.e., leptin, apelin, ghrelin, obestatin and orexins) have been discovered. Besides the central nervous system these regulatory peptides are produced and released by the gastrointestinal (GI) endocrine cells and neurons, and functional receptors were found in the GI tract and the pancreas. High expression of feed intake-regulating peptides was found in the stomach; however, they may be expressed in other GI tissues too. The peptides control gastrointestinal functions, modulate orexigenic drive and energy metabolism via different mechanisms. Basal leptin, apelin, ghrelin and obestatin plasma concentrations correlated with BMI, and we observed significant reduction of ghrelin and leptin concentrations following fundectomy in rats. We have shown previously that exogenous leptin and ghrelin (a peptide derived from the same preprohormone as obestatin) inhibit the secretion of rat pancreatic juice through a neurohormonal mechanism. Intravenous obestatin was found to stimulate pancreatic protein output in anaesthetized rat via a CCK-vagal-dependent mechanism, whilst a direct action of obestatin on rat pancreatic acini in vitro resulted in opposite effect. Intravenous boluses of apelin reduced the juice volume, protein and trypsin outputs in a dose-dependent manner. However, apelin administered into the duodenal lumen significantly increased pancreatic protein and trypsin outputs through a vagal mechanism. Orexin A and B were found to stimulate insulin release, though on the rat exocrine pancreas orexin A had no effect, and the effect of orexin B was weak. Concluding, feed intake-regulating peptides participate in controlling the exocrine pancreas.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.