Effects of citalopram on expression of B-cell lyraphoma/leukemia-2 and Bcl-associated X protein and neuron apoptosis in hippocmnpus CA1 and CA3 regions of long-term stress rats

Objective To explore effects of citalopram on preventing neuron apoptosis in CA1 and CA3 regions of hippocampus in chronic stress rats.Methods Forty male Sprague Dawley rats were randomly divided into five groups with eight each group.Stressed rat models were made by forced swimming daily for 4 weeks,and the stressed group wag treated with intragagtric administration of 0.9% sodium chloride,and three experimental groups with different dosage of citalopram.The fifth group was given no treatment as control.The proteins of bcl-2 and bax were detected with immunohistochemistry.Apoptosis cell number and integral optical density in CA1 and CA3 regions were tested and analyzed with terminal deoxynucleotidyl transferage biotin-dUTP nick end labeling(TUNEL)method and Nikon imaging software-BR(NIS-BR).Results The stationary time Wag longer in the stress group[(279±53)s]than the control group[(182 ±35)s],and the three citalopram treatment group[(200±71)s,(159±59)s,(165±54)s].The number of struggling[(20 ±3)times]was less than control group[(24 ±3)times]and the treatment groups[(37 ±16),(32 ±10),(24 ±4)times],and exhaustive time[(38.3 ±5.1)min]longer than control group[(22.9±1.8)min],shorter than treatment groups[(54.4 ±2.9)min,(69.3±17.6)min,(46.4±4.0)min].AlJ tIle differences were statistically significant(P＜0.05 or 0.01).Rats in the stress group showed more apoptotic cells,reduced expression of bcl-2 and increased bax protein expression in CA1 and CA3 regions(P＜0.05 or 0.01)in comparison with control group.Compared to the stressed group,rats in treatment groups showed Iess apoptotic cells,reduced expression of bax and increased bcl-2 protein expression in CA1 and CA3 regions(P＜0.05).Conclusion Long-term stress might cause neuron apoptosis and expression of bcl-2 and bax in CA1 and CA3 region of hippocampus,and citalopram might have prophylactic effects on this process. Key words: Citalopram; Hippocampus;  Stress;  Genes,bcl-2;  bcl-2-Associated X protein