PartI Estrogen May Reduce Mortality And Ischemic Damage Caused By Middle Cerebral Artery Occlusion In The Female Rat

Parti Estrogen may reduce mortality and ischemic damage caused by middle cerebral artery occlusion in the female rat[Abstract] Objective To study the neuroprotective effects of estrogen on focal cerebral ischemia rats. Methods 60 female SD rats were randomly divided into three 'groups ,sham-operated group,ovariectomized group(OVX),OVX and treated with 17|3-estrodiol group(E2+OVX). Permanent focal ischemic models were made with thread embolism of middle cerebral artery. Accumulating mortality,infarct volume ratio were analysed statistically among three groups. Results the mortality of three groups were 15%(3/20);45%(9/20);10%(2/20) individually. The infarct volume ratio of "three groups were 41.69+2.53%;52.45+1.55%;36.69+3.29% individually. OVX rats had a higher mortality than sham-operated group and E2+OVX group(P<0.05) ,OVX rats had a larger infarct volume ratio than sham-operated group(P<0.05)and E2+OVX group(P<0.01). Conclusion Estrogen can decrease the Accumulating mortality and infarct volume ratio ,it may exerts neuroprotection on focal cerebral ischemia through inhibiting cell apoptosis and protecting the penumbral zone.PartII Interleukin-1 B gene expression after focal stroke in rats [Abstract] Objective To investigate the gene expression of IL-1 B and its receptor (IL-lRs)and receptor antagonist(IL-lRA) after focal stroke in rats.Methods Quantitative reverse transcription and polymerase chain reaction(RT-PCR) technique was used to examine the mRNA expression profile of IL-1 P ,IL-1RA and twe IL-1R isoforms after permanent occlusion of the middle cerebral artery(MCAO) in rats. Results IL-1 P mRNA expressed very early in ischemic cortex at all time points and greatly increased between 12 hours and 24 hours;the expression of IL-lRAmRNA peaked at 48 hours and remained elevated up to 5 days;IL-RImRNA was relatively highly expressed in normal cortex and was further elevated late after ischemic injury;In contrast,IL-RII mRNA only expressed in ischemic cortex,reaching peak levels between 24 hours and 48 hours. Conclusions The gene expression of IL-1 P and its receptor (IL-lRs)and receptor antagonist(IL-lRA) after focal stroke were all elevated,Differential expression of IL-1 P ,IL-1RA,IL-RI and IL-R II mRNAs after focal stroke may suggest a distinct role(s) for each component of the IL-1 systems in ischemic injury.Part III The effects of estrogen on gene expression of IL-1 3 after focal stroke in rats[Abstract ] Objective To investigate effects of estrogen on the expression of IL-1 P and its receptor antagonist(IL-lRA) after focal stroke hi rats. Methods 12 cases of rats were divided into three groups :false operative group,OVX group,OVX+E2 group;Quantitative reverse transcription and polymerase chain reaction(RT-PCR) technique was used to examine the mRNA expression profile of IL-1 P,IL-1RA after permanent occlusion of the middle cerebral artery(MCAO) inrats. Results IL-1 P mRNA expression in OVX group increased comparing with that in false operative group (PO.05),IL-1 P mRNA expression in OVX+E2 group decreased comparing with that in OVX group(P<0.05),and IL-1 P mRNA expression had no significant difference between OVX+E2 group and false operative group (P>0.05);IL-lRAmRNA expression in three groups had no statistical difference (P>0.05) . Conclusions Estrogen inhibit the expression of IL-1 3 mRNA after .focal cerebral ischemia,this may be one of the mechanisms which Estrogen exerts its neuroprotection in focal cerebral ischemia.PartW The effects of estrogen on cell apoptosis and expression of Bcl-2 and Bax after focal stroke[ Abstract 1 Objective To investigate effects of estrogen on cell apoptosis and the expression of bcl-2. and bax after focal stroke in rats. Methods 48 cases of rats were divided into three groups :2h group,24h group,48h group;Every group was divided into 3 subgroups,they were false operative group,OVX group,OVX+E2 group;Irnmunohistochemistry TUNEL staining and Quantitative reverse transcription and polymerase chain reaction(RT-PCR) technique were used...