ABSTRACT
Objective To investigate the effect of 17β-estradiol on the pain threshold in neuropathic rats.Methods Fifty fe-male SD rats were divided into five groups by adopting the random number table method,the sham operation group(separating and exposing the left sciatic nerve without ligation and giving the saline injection),the other four groups were established as chronic compression injury(CCI)model of sciatic nerve:CCI group(saline injection),estradiol group(17β-estradiol injection),antagonist group(AP-5 injection)and composite group(17β-estradiol and AP-5 injection),10 cases in each group.The rat mechanical pain threshold value was examined by adopting the paw withdrawal mechanical threshold(PWMT),the rat thermal threshold was exam-ined by adopting the paw withdrawal thermal latency(PWTL),and the expression of NMDAR1 protein was determined by immuno-histochemistry and Western blot.Results Compared with the sham operation group,PWM T in the CCI group and estradiol group was decreased(P<0.05)and PWTL was shortened(P< 0.05),while the expression of NMDAR1 protein was significantly in-creased(P<0.05).Compared with the CCI group,PWMT in the estradiol group was decreased(P<0.05)and PWTL was short-ened(P<0.05),while the expression of NMDAR1 protein was significantly increased(P<0.05).Conclusion 17β-estradiol can de-crease the pain threshold of the neuropathic pain rats by increasing the NMDAR1 expression.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the neuroprotective effects of baicalin against hypoxia and glucose deprivation-reperfusion (OGD/RO)-induced injury in SH-SY5Y cells.</p><p><b>METHODS</b>SH-SY5Y cells were divided into a control group, a OGD/RO group, which was subject to OGD/RO induction; and 3 baicalin groups subject to baicalin (1, 5, 25 μmol/L) for 2 h before induction of OGD/RO (low-, medium-, and high-dose baicalin groups). Cell viability was detected by thiazolyl blue tetrazolium bromide (MTT) assay and flow cytometric analysis was used to detect cell apoptosis. Real-time polymerase chain reaction was performed to determine the mRNA expression of caspase-3 gene. Western blot analysis was conducted to determine the expression of nuclear factor (NF)-κB and N-methyl-daspartic acid receptor-1 (NMDAR1).</p><p><b>RESULTS</b>Baicalin could significantly attenuate OGD/RO mediated apoptotic cell death in SH-SY5Y cells; the apoptosis rates in the low-, medium- and high-dose groups were 12.1%, 7.9%, and 5.4%, respectively. Western blot and real-time PCR analysis revealed that significant decrease in caspase-3 expression in the baicalin group compared with the OGD/RO group (P<0.01). Additionally, down-regulation of NF-κB and NMDAR1 was observed in the baicalin group compared with those obtained from the OGD/RO group. Compared with the low-dose baicalin group, remarkable decrease was noted in the medium- and high-dose groups (P<0.01).</p><p><b>CONCLUSION</b>Baicalin pre-treatment attenuates brain ischemia reperfusion injury by suppressing cellular apoptosis.</p>