Showing 3 results for Changizi Ashtiyani
Saeid Changizi Ashtiyani , Saeid Khameneh, Hamid Salimi Khaligh ,
Volume 3, Issue 2 (Summer 2000)
Abstract
Arterial baroreflexes are the most important mechanism of cardiovascular system that can respond to rapid blood pressure changes during everyday activities. In this study we have assessed adaptive responses of carotid baroreflexes during isometric & dynamic exercise and compared the results with acute response during rest. The applied work loud in dynamic exercise was 100 watts and in isometric exercise it was 50% of calculated maximum force. Experiments were performed on 12 young male healthy sedentary volunteers aged between 21-28. This study was done in three exercises. In all three protocles, adaptation process during stimulation was assessed by studying of beat to beat R-R interval of ECG. In order to stimulate the carotid baroreceptors neck suction device Eckberg model was used and duration of stimulation was 10 seconds. ECG was taken carefully. Examination of adaptive process during stimulation showed maximal response achieved in resting state is statistically significant compared with that of isometric and dynamic exercise respectively (P<0.038, P<0.007). where as, comparison of adaptive response of rest state with isometric exercise and dynamic exercise was not statistically significant. There is no significant relation between maximal and adaptative response in dynamic and isometric exercises, although in general adaptative process in resting state compared with isometric and dynamic exercise was more pronounced. This observation confirmed that Vagal withdrawal with alimited degree of sympathic stimulation are challenged in this phenomenon. In other words the Sa response to vagal stimulation is related by sympathic stimulation.
Hoshang Nagafi, Saeed Changizi Ashtiyani, Saeed Khamene,
Volume 14, Issue 3 (7-2011)
Abstract
Arterial baroreceptors are located in the carotid and aortic arteries and play a pivotal role in rapid control of cardiovascular system. The purpose of this article is to review the effects of baroreceptors stimulation on heart rate at rest and during exercise and cerebral blood flow rate in young and middle aged male and female individuals. There is ample evidence indicating that the arterial baroreflex remains functional during exercise by readjustment which is in direct relation to the intensity of exercise. These adjustments might be done through somatosensory afferents from peripheral regions of the body, pathways obeying central command neurons, or vasopressin and oxytocin pathways that converge into the nucleus tractus solitarii (NTS). Cerebral blood flow autoregulation is a process by which cerebral blood flow is maintained at a fixed rate despite fluctuations in cerebral perfusion pressure. Similar to that in young individuals, this mechanism, despite fluctuations in baroreceptors sensitivity, stabilizes cerebral blood flow rate in a certain range in middle-aged individuals, although with aging the absolute cerebral blood flow rate decreases in both genders. In addition, it has also been shown that after termination of carotid baroreceptors stimulation, heart rate increases which is known as postvagal tachycardia (PVT). It seems that two components, adrenergic and non-adrenergic, are involved in PVT.
Saeed Changizi Ashtiyani, Ali Zarei, Mehrdad Shariati, Jabary, Hasan Ghasemi,
Volume 14, Issue 5 (11-2011)
Abstract
Background: Physalis Alkekengi is a perennial plant with a creeping and ryzumy stem belonging to the solanaceae family. This study investigates the possible effects of Physalis Alkekengi on plasma concentrations of some biochemical factors.
Materials and Methods: Fifty male Wistar rats weighing an average of 190 ± 5 g were divided into five groups of ten: Control group without receiving any substances, control group with 2.0 ml/dl administration of the solvent, and three experimental groups receiving 0.4 (maximum), 0.2 (medium), and 0.1 (minimum) g/kg intra-peritoneal (IP) injections of the drug. The intra-peritoneal (IP) injection of the drug was done for 14 days and after this period, for conducting lab tests, blood sampling was done and the results were analyzed through ANOVA and Tukey test.
Results: According to the results, protein and albumin plasma concentrations showed a significant increase (P<0.05) while creatinine plasma concentration, bilirubin, and urea nitrogen (BUN) did not reveal any significant changes.
Conclusion: This family of plants contains significant amounts of glucocorticoids, such compounds are likely to increase liver and plasma proteins. In addition, due to the presence of compounds, such as physaline, vitamin C, and albumin, this extract is likely to increase blood pressure and, eventually, increase glomerulic refinement and diuretic properties therefore, the absence of significant increases in plasma concentrations of the substances produced by metabolism in plasma seems reasonable
