The Apolipoprotein Jmrna Expression In A Rat Model Of Cerebral Infarction

OBJECTIVE To investigate the mechanism of the neuro-protective effect of apoJ in rat acute cerebral infarction.METHODS 70 healthy male SD rats were devided randomly into normal control group (group NC), sham-oprated group (group SO), cerebral ischemia 6 hours group (group 6h), 24 hour group (group 24h), 3 day group (group 3d ), 5 day group (group 5d) and 7 day group (group 7d). Permanent cerebral infarction models were prepared by occluding the middle cerebral artery (MCA) using thread embolizing and were juged by neurological score and TTC staining. Brain water content (BWC) was measured, and the C3 and apoJ mRNA expression were analyzed by RT-PCR. RESULTS1. Brain water contentNo different BWC was observed between the normal control group and sham-operated group (.P>0.05). But each operated group there is a higher BWC than that of normal control group and sham-operated group (P<0.01). And comparing with other operated groups, the BWC of 3 days group is the highest obviously (P<0.01).2. The expression of C3 mRNAA low level C3 mRNA was detected in normal control group and sham-operated group, and no difference was observed between them (P>0.05). C3 mRNA expression was found to be increased at 6 hours postcclusion and reached a peak level at 3 days after the onset of cerebral ischemia (3.9 times that of normal control group). And a statistically significant difference was found between any other group and group 3d (PO.01).3. The expression of apoJ mRNALow levels C3 mRNA were detected in normal control group, sham-operated group and group 6h, and no statistically significant differences were observed among them (/>>().05). A increased apoJ mRNA expression appeard in group 24h and the peak level was foundinin group 3d (2.3 times that of normal control group).4. correlation analysisA positive correlation was found between C3 mRNA expression and BWC and a negative correlation between apoJ mRNA expression and BWC(R=0.263 and - 0.212 respectively, PO.05), and the apoJ mRNA expression was correlated positively to that of C3 (R=0.509, P<0.01).CONCLUSIONS1. Rat brain water content was increased to a peak at day 3 in cerebral infarction animal models.2. Comolement may be involved in the neuron necrosis in rat acute cerebral infarction.3. Increased apoJ expression may be invoved in neuroprotective in cerebral infarction by inhibiting the complement activation.