磷酸二酯酶4抑制剂咯利普兰逆转慢性酒精中毒及戒断诱导的小鼠抑郁样行为

摘要

AIM:To investigate the effect of phosphodiesterase 4 (PDE4) inhibitor rolipram on the levels of cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP response element-binding protein (CREB), phosphorylated CREB (p-CREB) and brain-derived neurotrophic factor (BDNF) in the hippocampus and the prefrontal cortex (PFC) of alcoholism model mice.METHODS:The mice (n=60) were randomly divided into control group , con-trol+rolipram group, alcoholism model group, and alcohol +rolipram (0.1, 0.5 and 1 mg/kg) groups.The mice were given alcohol preference test on days 6, 13, 20 and 27.After the test, the mice received withdrawal of alcohol for 1 d.On day 28, the mice were given behavior test of depression , and after the test, the mice were sacrificed.The cAMP levels in the hippocampus and PFC were detected by ELISA , and the protein levels of PKA , CREB, p-CREB and BDNF were detec-ted by Western blot.RESULTS:The mice showed an obvious drinking phenomenon (P<0.01), and the immobility time of forced swimming test and tail suspension test was significantly increased (P<0.01), with increasing drinking days and withdrawal times .However , chronic treatment with rolipram for 28 d reversed this phenomenon .Moreover , the cAMP lev-els in the hippocampus and PFC were significantly decreased after 28 d alcohol treatment ( P<0.01 ) , and pretreatment with rolipram (1 mg/kg) obviously reversed this decrease (P<0.01).Parallel to these changes of cAMP , the protein lev-els of PKA, p-CREB and BDNF were also decreased in the hippocampus and PFC (P<0.01), and 28 d rolipram adminis-tration inhibited the decreased cAMP , PKA, p-CREB and BDNF levels in the hippocampus .Moreover, 28 d rolipram ad-ministration also reversed decreased cAMP , PKA and p-CREB in the PFC.CONCLUSION:Rolipram treatment protects against alcohol-induced depression-like behaviors , and also reduces alcohol drinking .These effects may be related to PDE4-cAMP-PKA-CREB-BDNF pathway .%目的：研究磷酸二酯酶4（PDE4）抑制剂咯利普兰对酒精中毒戒断诱导的抑郁样行为的作用及对小鼠海马和前额叶皮质脑区环磷酸腺苷（cAMP）、蛋白激酶A（PKA）、cAMP反应元件结合蛋白（CREB）、磷酸化CREB（ p-CREB）和脑源性神经营养因子（ BDNF）表达的影响。方法：取60只雄性ICR小鼠，随机分为空白对照组、空白＋咯利普兰组、慢性酒精模型组和咯利普兰治疗组（0．1、0．5和1 mg／kg）。给予酒精28 d，期间每周进行酒精戒断处理。慢性酒精处理后，进行强迫游泳测试（ FST ）和悬尾测试（ TST ），观察小鼠抑郁样行为；ELISA检测小鼠海马和前额叶皮质cAMP含量，Western blot 检测小鼠海马和额叶皮质PKA、CREB、p-CREB和BDNF的表达。结果：随着饮酒天数及戒断次数的增加，小鼠表现出明显嗜酒现象，饮酒量增加（ P＜0.01）， FST和TST测试中的不动时间增加（P＜0.01）。小鼠给药咯利普兰（0.5和1 mg／kg）28 d后，FST和TST不动时间与模型组相比明显减少（P＜0.05），且能改善小鼠的嗜酒现象，小鼠饮酒量与模型组相比明显减少（P＜0.01）；相比于正常组，模型组小鼠海马和前额叶皮质cAMP含量明显降低（ P＜0.01），并且海马和额叶皮质PKA、p-CREB和BDNF也明显低于正常水平（P＜0.01）。咯利普兰（0.5和1 mg／kg）给药28 d后，海马与前额叶皮质cAMP含量明显增加（P＜0.01），酒精抑制的海马脑区PKA、p-CREB和BDNF表达被逆转（P＜0.05），且酒精抑制的前额叶皮质PKA和p-CREB表达被逆转（ P＜0.05）。结论：磷酸二酯酶4抑制剂咯利普兰能明显改善酒精中毒及戒断引起的抑郁样症状，且能减轻嗜酒症状，机制可能涉及第二信使cAMP通路。咯利普兰通过抑制PDE4，增加海马与前额叶皮质cAMP水平，进而激活PKA-CREB-BDNF通路，从而产生抗抑郁作用。