【摘要】 目的:探讨大鼠侧脑室注射胆碱能激动剂氨甲酰胆碱(carbachol,CBC)后蓝斑儿茶酚胺能神经元活性和血管紧张素能AT1受体表达的变化以及阻断AT1受体对上述变化的影响。方法:选用SD雄性大鼠,利用免疫组织化学方法,观察侧脑室注射氨甲酰胆碱(0.5μg)和/或losartan(20μg)后40min,蓝斑的酪氨酸羟化酶(tyrosine hy-droxylase,TH)及AT1受体免疫反应活性的变化。结果:侧脑室注射氨甲酰胆碱(0.5μg)后40min,蓝斑的TH及AT1受体免疫反应阳性神经元数目明显增多(P<0.05),免疫染色强度明显增强(P<0.05)。losartan预处理后蓝斑的TH免疫反应活性和AT1受体表达明显下降(P<0.05)。结论:侧脑室注射胆碱能激动剂氨甲酰胆碱对蓝斑儿茶酚胺能神经元具有兴奋作用,AT1受体表达增强;阻断脑血管紧张素能AT1受体可下调氨甲酰胆碱在蓝斑诱导的上述变化。更多还原

【Abstract】 Aim and Methods: In the present study, we investigated the TH immunore ac tivity and the expression of angiotensin AT₁ receptor in locus coeruleus after intracerebroventricular（i.c.v.） injection of carbachol in conscious SD rats wit h immunohistochemistry. Meanwhile the effects of blocking AT₁ receptor were al so observed. Results: Both mean optical density and number of TH and AT₁ immunoreactive positive neurons were markedly increased in locus coer uleus after 40 minutes of i.c.v. injection of carbachol（0.5 μg） . The enhanceme nt was significantly reduced by i.c.v. injection of losartan. Conclusion : The results above suggest that i.c.v. injection of cholinergic agonist carbachol can enhance the activity of adrenergic neurons and the expression of AT₁ receptor in locus coeruleus. The blockade of AT₁ receptor may down regul ate the above action induced by carbachol in locus coeruleus.更多还原