清醒自由活动大鼠下丘脑后部内源性γ－氨基丁酸的释放

Release of endogenous γ-aminobutyric acid in the posterior hypothalamys of freely moving conscious rat

清醒自由活动大鼠下丘脑后部内源性γ－氨基丁酸的释放郭莲军（武汉同济医科大学基础医学部药理教研室，武汉４３００３０）γ－氨基丁酸（γ－ａｍｉｎｏｂｕｔｙｒｉｃａｃｉｄ，ＧＡＢＡ）作为一种抑制性神经递质广泛分布于中枢神经系统，下丘脑后部含有大量的ＧＡＢＡ...

Push-pull superfusion was used to in-vestigate the release of cndogenous γ-aminobutyricacid(GABA)from the posterior hypothalamus of thefreely moving conscious rat at basal conditions and inresponse to centrally applied drugs.After an initial,exponential decline,the release rate of GABAremained fairly constant for many hours.Fluctuationsinthe release rate of GABA point to the existence of anultradian rhythm with an approximate frequency of 1cycle per 70 min.Hypothalamic superfusion with apotassium-rich(50,90 mmol·L-1)artificialcerebrospinal fluid led to a concentration-dependentincrease in the GABA release.Hypothalamicsuperfusion with the tetrodotoxin(1μmol·L-1)led toa long-lasting decrease in the GABA release.