茶氨酸经下丘脑腹外侧核抑制雌性小鼠摄食与胃排空作用研究

Theanine Depressed the Food Intake and Gastric Emptying in Female Mice via Lateral Hypothalamic AMPA and NMDA Receptor

采用比色法观察脑室、核团内微注射和腹腔注射茶氨酸对外周胃排空的影响。结果表明，腹腔给予茶氨酸3~30 mg/kg后显著抑制摄食量和胃排空；脑室给药3~100 ng后，对胃排空的影响表现出V型曲线，3~30 ng茶氨酸剂量依赖性抑制胃排空，50、100 ng茶氨酸使胃排空恢复到正常水平。然而，腹腔注射同样量的茶氨酸并无抑制作用。在下丘脑外侧核内注射同量茶氨酸，出现与脑室内类似的抑制胃排空作用，在弓状核、下丘脑腹内侧核内注射却无明显的改变。在下丘脑外侧核内注射NMDA和AMPA后均能诱导摄食和胃排空的增加，而茶氨酸10、30、100 ng能抑制两者诱导的胃排空及 NMDA诱导的摄食，茶氨酸3~100 ng能抑制 AMPA诱导的摄食。上述结果表明茶氨酸抑制摄食和胃排空作用可能与抑制下丘脑外侧核的NMDA受体和AMPA受体有关。

In the present study, the food intake and gastric emptying of female mice were evaluated after theanine microinjection in cerebral ventrile, lateral hypothalamus, arcurate nuleius and ventromedial hypothalamic nucleus. Results showed that theanine 3~30 mg/kg intraperitoneal injection decreased food intake and gastric emptying;theanine 3~100 ng microinjection into cerebral ventrile induced “V” style effects on gastric, theanine 3~30 ng decreased gastric emptying dose-dependently while theanine 50 and 100 ng recovered gastric emptying. Theanine microinjection in lateral hypothalamus displayed similar effects on gastic emptying as theanine i.c.v while microinjection in arcurate nucleus and ventromedial hypothalamic nucleus did not alert gastric emptying. Theanine decreased food intake and gastric emptying induced by NMDA and AMPA microinjection in lateral hypothalamus. It was concluded that theanine depressed the food intake and gastric emptying after microinjection in lateral hypothalamus via NMDA and AMP receptor, partly.