一种通过选择离子监测测定脑内生物胺的简单方法：其在阐明3-碘-L-酪氨酸诱导催乳素释放机制中的应用。

A simple procedure for the assay of brain biogenic amines by selected-ion monitoring: its application to the elucidation of the mechanism of prolactin release induced by 3-iodo-L-tyrosine.

作者信息

Smythe G A, Brandstater J F, Bradshaw J E, Lazarus L

出版信息

Aust J Biol Sci. 1979 Jun;32(3):335-41. doi: 10.1071/bi9790335.

Abstract

A simple method for the assay of brain biogenic amines by selected-ion monitoring was applied to examination of the effects of 3-iodo-L-tyrosine on the hypothalamic-median eminence concentrations of dopamine, noradrenaline and serotonin in the rat. Thirty minutes after its administration iodotyrosine (50 mg/kg) caused a highly significant (P less than 0.0005) rise in serum prolactin and a highly significant (P less than 0.0025) fall in the concentration of dopamine in the hypothalamus and median eminence where the levels reached 50% of control levels. Less marked but significant falls were also observed in the hypothalamic (P less than 0.05) and median eminence (P less than 0.0025) concentrations of noradrenaline after iodotyrosine administration. Serotonin concentration was significantly reduced (P less than 0.025) in the median eminence but not in the hypothalamus after iodotyrosine administration. These findings suggest that iodotyrosine exerts its prolactin stimulating effect by blockage of dopamine synthesis rather than by receptor blockade.

摘要

一种通过选择离子监测来测定脑内生物胺的简单方法被应用于研究3-碘-L-酪氨酸对大鼠下丘脑-正中隆起中多巴胺、去甲肾上腺素和5-羟色胺浓度的影响。给予碘酪氨酸（50mg/kg）30分钟后，血清催乳素显著升高（P<0.0005），下丘脑和正中隆起中多巴胺浓度显著下降（P<0.0025），降至对照水平的50%。给予碘酪氨酸后，下丘脑（P<0.05）和正中隆起（P<0.0025）中的去甲肾上腺素浓度也出现了不太明显但显著的下降。给予碘酪氨酸后，正中隆起中的5-羟色胺浓度显著降低（P<0.025），但下丘脑中未降低。这些发现表明，碘酪氨酸通过阻断多巴胺合成而非受体阻断发挥其催乳素刺激作用。