| As a type of important intrinsic substance, prostaglion El also called alpros-tadil, an eicoane coponent, which is produced from DHLA, has a variety of effects such as vessel dilation, blood pressure regulation, platelet congregation inhibition microcirculation improvement artry sclerosis delayinm and immunal regulation. The plasmatic ETincreases when cerebral infarction occurs.The underlying reason is stimulated by ischemia and insufficient oxygen supply.And the stress reation induced by infarction causes and TXA2 increases, which leads to increase of ET releasing. In the ischemic area,the endothelastands less pressure than normal and then is stimulized to produce more ET. High level of ET-caused sustained constriction of cerebral arteries and meanigeal arteries, which exaggerates hypoxia and ischemic of brain tissure. thus a vicious circle is formed, therefore it is suggested that ETis involved in the process of cerebral infarction and it is a potential index for monitoring cerebral infarction. ET is the most effective long term vessel constrictor sofar. And the antagonist cGRPis the most effective vessel dialator sofar. The vesseldialating mechanism of cGRPis dim. The most popular explanations for that are ①cGRP directly dialate vessels. ②)cGRP works via c - AMP. ③It activate K - ATP channel on smooth muscle. ④N - type and P - type voltage sensitive channel of neurons may be involved in cGRP. ⑤cGRP might maintain Ca stability in cells. The antagonizing ET and cGRP are universally founded in neurolycal and circulatory tissuus. They are the substances that catch most attention in recent years. So the protective and thera-...
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