ABSTRACT
Background: Stroke is the most important reason of cerebral ischemia and following reperfusion lead to programmed cell death. Harm to hippocampus causes major disruption in the performance of active memory tests. So in this study, we investigated the effect of losartan [angiotensin antagonists II] on spatial memory deficits and neuronal damage caused by ischemia /reperfusion in rats
Materials and methods: In this experimental study, animals were divided into 4 groups as follow: control, ischemia, experimental and vehicle. 20 minutes before ischemia, 5mg/kg losartan was injected to animals in experimental group. Ischemia was done by both common carotid occlusion for 20 minutes followed by reperfusion. After a week, rats were tested by Morris water maze and histological changes of CA1 pyramidal cells were studied by Nissl and Tunnel staining
Results: Results of Morris water maze showed significant difference between control and ischemia groups, while this difference was not significant between control and experimental groups. There was significant difference in the number of viable pyramidal neurons and apoptotic cells in CA1 region of hippocampus between control and experimental groups compared with vehicle and ischemia groups
Conclusion: 5mg/kg losartan improves pyramidal cells and histological changes of CA1 region caused by ischemia/ reperfusion and can prevent apoptosis, but this dose cannot reduce behavioral disorders caused by cerebral ischemia
ABSTRACT
The short break in cerebral blood flow causes permanent brain injury and behavioral dysfunction. The hippocampus, specifically the CA1 pyramidal cells, is highly vulnerable to ischemic injuries. There is no effective pharmacological strategy for improving brain tissue damage induced by cerebral ischemia. Previous studies reported that pentoxifylline has a neuroprotective effect on brain trauma and it is well known that endogenous estrogen improves stroke outcome during vascular occlusion. In this study, the possible positive effects of pentoxifylline and estrogen on behavioral deficit and neuronal damage were studied in female Wistar rats in estrous phase subjected to an experimental model of transient global brain ischemia. In this experimental study, female Wistar rats [n= 56] were assigned to control, ischemia, vehicle, and pentoxifylline - treated [200 mg/kg IP] groups and all of them were in their estrous phase. Pentoxifylline was administered at 1 h before and 1 h after ischemia. Global cerebral ischemia was induced by bilateral common carotid artery occlusion, followed by reperfusion.Morris water maze and nissl staining was used for all groups. According to Morris water maze test results, cerebral ischemia could not exert any negative effect on cognitive spatial abilities after reperfusion and there were no significant differences between groups. In Nissl study, there were significant differences between number of pyramidal cells in both control and pentoxifylline - treated groups [P
ABSTRACT
Cerebral ischemia is known as a main cause of morbidity and mortality in the world and there was no effective treatment yet. Global cerebral ischemia causes loss of pyramidal cells of brain cortex following global ischemic/reperfusion. Recently, using immunophilin ligands has been considered as a potential and appropriate strategy for neuroprotection. Since it was observed that tacrolimus [FK506], a useful immunosuppressant used in organ transplantation, provides neuroprotection and prevents neuronal damage,the importance of immunophilins in the development of neuroprotectors has emerged. In this study, we investigated the neurotrophic effect of the immunosuppressant agent FK506 in rat after global cerebral ischemia. In this experimental study, 25 Wistar rats were assigned to control [intact], ischemia and 3 FK506 treated [1, 3, 6 mg/kg] groups. Both common carotid arteries were occluded for 20 minutes followed by reperfusion. In 3 experimental groups, tacrolimus or FK506 was given as a single dose exactly at the time of reperfusion respectively as 1, 3, 6 mg/kg by intravenous administration [IV]. The same doses repeated by intraperitoneally administration [IP] 48 hours after reperfusion. After 4 days, the rats were sacrificed and brain sections were stained by H and E and Nissl. Our findings showed that 20 min ischemia decreased the number of the cortex pyramidal cells. But there were significant differences between number of cortex pyramidal cells in ischemia and FK506 [6mg/kg] groups. Our study suggests that tacrolimus has a neurotrophic effect on pyramidal cells of brain cortex and may candidate for treatment of ischemia brain damage
ABSTRACT
Cerebral ischemia is known as a major problem in the world. Reperfusion following the ischemia ultimately leads to programmed cell death or apoptosis. Specific regions of the brain and certain types of neurons are more susceptible to cerebral ischemia, such as pyramidal neurons of CA1 region of hippocampus. Recently, using of immunophilin ligands has been considered to be a potential and appropriate strategy for neuroprotective and neurogenitor activity. Up to now, the right time of injection for providing the suitable effect on pyramidal cells of CA1 has not been assessed precisely. In this study, the neurotrophic effects of tacrolimus on CA1 cells were studied on 40 male Wistar rats in 8 experimental groups. Ischemia model was induced by ligation of bilateral common carotid arteries. For detecting the most appropriate time for 6mg/kg, Injection was done via single and double doses with intervals of 6, 24, 48 and hours. The repeated doses of 6mg/kg with interval of 48 hours are the suitable dose and time of injection. It seems that tacrolimus can be an appropriate strategy as a neurotrophic drug for treating brain ischemia
Subject(s)
Male , Animals, Laboratory , Tacrolimus/pharmacology , Hippocampus/drug effects , Rats, Wistar , CA1 Region, Hippocampal/drug effects , Brain IschemiaABSTRACT
Ecstasy is a psychoactive, hallucinogen drug and a member of amphetamines family and is used commonly worldwide. Ecstasy overdose leads to restlessness, anxiety, hallucination, cardiovascular disorders and liver toxicity. Recently, the use of vasodilators, such as pentoxifylline [PTX], is one of the new strategies for protection against liver lesions caused by some substances such as alcohol consumption. There are few studies about the protective effect of pentoxifylline on liver damages due to MDMA long administration. Therefore, a comprehensive study on the protective effect of pentoxifylline on liver lesions caused by prolonged use of ecstasy seems to be necessary. This experimental study was performed on five groups: control, Ecstasy [7.5 mg/kg], Experimental 1 [100 mg/kg PTX simultaneously with the last dose of Ecstasy], experimental 2 [100 mg/kg PTX a week before Ecstasy injection], and vehicle [normal saline] groups [n=25]. After two weeks, animals were killed and their livers were prepared for histological studies [H and E method] and TUNEL technique for investigating of apoptotic bodies. The apoptotic bodies and hepatocytes lesions in experimental group 1 were lower than the other groupsm except control. It seems that the use of pentoxifylline after consumption of pure ecstasy can decrease tissue damage and prevent the induction of apoptosis in rat liver
Subject(s)
Animals, Laboratory , Rats, Wistar , Pentoxifylline , Pentoxifylline/pharmacology , Apoptosis , Liver , Hepatocytes/drug effectsABSTRACT
The dorsalis pedis artery [DPA] is usually described as a continuation of the anterior tibial artery [ATA]. It turns into the sole and participates in plantar arch formation at the base of the first interphalangeal space. After dissecting the lower limb of a 44 year old male cadaver, it was revealed that the dorsalis pedis artery is passing to the lateral of the foot. It had changed its direction to the medial of the foot as a arcuate artery. Awareness of these variations is very important for specialist to prevent the artery from any damages in surgical techniques, such as ankle arthroscopy. On the other hand, attention to these variations is very essential in diagnosing of common iliac artery thrombosis
ABSTRACT
Arterial variations can cause many problems in treatment of patients. So, it seems that knowledge about these variations can improve the process of treatments. During dissection of a 55 year-old male cadaver, it was seen that radial artery had been separated from the second part of axillary artery and brachial artery had been continued in forearm as ulnar artery. This variation is important because radial artery is used for injection of drugs, catheterization and bypass grafting of coronary arteries. Attention to this variation may facilitate the surgical approaches and decrease the risk of arterial injuries in upper limb