γ-氨基丁酸A受体对新生大鼠基本节律性呼吸的调节作用  

Modulatine Role of Gamma-Aminobutyric Acid A Receptor on Respiratory Rhythmical Discharge Activity in Brainstem Slice of Neonatal Rat

作　　者：千智斌[1] 姬明丽[2] 齐莹[1] 吴中海[1] 

机构地区：[1]南方医科大学生理学教研室 [2]新乡医学院病理生理学教研室,河南新乡453003

出　　处：《实用儿科临床杂志》2008年第6期460-462,共3页Journal of Applied Clinical Pediatrics

基　　金：国家自然科学基金项目资助(30570670);广东省自然科学基金项目资助(5004714)

摘　　要：目的探讨γ-氨基丁酸A(GABAA)受体对新生大鼠基本节律性呼吸的产生和调节作用。方法制备新生大鼠离体延髓脑片标本,包括面神经后核内侧区(mNRF),并保留舌下神经根,予灌流改良Kreb′s液(MKS),记录舌下神经根的呼吸相关节律性放电活动(RRDA)。实验分为3组,每组分别使用6只脑片标本。GABA量效关系组:以10、20、40、60μmol/L的GABA灌流脑片,加药前神经放电为对照组,观察RRDA的变化,描记量效曲线,选择最适质量浓度;荷包牡丹碱(bicuculline)组:以10μmol/L bicucul-line灌流脑片,观察RRDA的变化;GABA和bicuculline组:联合应用40μmol/L GABA和10μmol/L bicuculline灌流脑片,观察RRDA的变化。结果GABA对延髓脑片RRDA有抑制作用,使用含GABA的MKS灌流脑片标本可使RRDA的吸气时程(TI)缩短、放电积分幅度(IA)下降、呼吸周期(RC)延长、呼气时程(TE)延长。40μmol/L的GABA对TI、IA、RC、TE等呼吸指标综合效果最显著。GABA可使RRDA的TI缩短、IA下降、RC和TE延长。bicuculline使TI延长、IA增加、RC和TE缩短,对RRDA有兴奋作用。联合使用GABA和bicuculline对RRDA无明显作用。结论生理条件下内源性GABA通过GABAA受体对新生大鼠的基本呼吸节律的产生和调节发挥重要作用。Objective To explore the modulation roles of gamma- aminobutyric acid A （GABAA ） receptor on respiratory rhythmical discharge activity in brainstem slice of neonatal rats. Methods Experiments were performed on in vitro neonatal rats brainstem slices. The slices containing the medial region of the nucleus retrofacialis（ mNRF）with the hypoglossal nerve rootlets retained was prepared in which the respiratory - related rhythmic discharge activity （RRDA） were recorded from hypoglossal nerve rootlets by suction electrode. The possible role of GABAA receptor on RRDA was investigated by administration of GABA and its antagonist bicuculhne in modified Kreb＇s solution（MKS） ,for perfusion of the brainstem slices. Eighteen slices positive of RRDA were randomly divided into three equal groups：the first group of slices was perfused with different concentrations（ 10,20,40,60 μmol/L） GABA and the most effective concentration was selected ;the second group of slices was perfused with 10 μmol/L bicuculline;the third group of slices was perfused with 10 μmol/L bicuculline plus 40 μmol/L GABA. The RRDA in 3 groups were observed. Results GABA decreased RRDA ,40 μmol/L was the most effective concentration. It shortened inspiratory time （TI）, decreased integral amplitude（ IA）, prolonged respiratory cycle （RC） and expiratory time （TE） respectively. By contrast, 10 μmol/L bicuculline produced opposite effects on RRDA, it prolonged TI, increased IA, shortened RC and TE respectively. 40 μmol/L GABA plus 10 μmol/L bicuculhne had no significant effects on RRDA. Condusion GABA plays an important role in modulate RRDA of neonatal rats via GABAA receptor.

关 键 词：面神经后核内侧区 呼吸相关节律性放电活动 Γ-氨基丁酸A受体 延髓脑片 

分 类 号：R33[医药卫生—人体生理学]