摘要
以Ｓｐｒａｑｕｅ－Ｄａｗｌｅｙ大鼠为实验动物，从出生后第１天起，每日皮下分别注射氨基肽酶的抑制剂Ｂｅｓｔａｔｉｎ〔１ｍｇ／ｋｇ（ｂ．ｗ）〕以及纳络酮〔２ｍｇ／ｋｇ（ｂ．ｗ）〕＋Ｂｅｓｔａｔｉｎ〔１ｍｇ／ｋｇ（ｂ．ｗ）〕，对照组注射等量的生理盐水，连续注射１４天。观察：１６日龄幼鼠的吸乳迷津分辨学习（ＡＤＬ），３０日龄Ｙ迷津明暗分辨学习（ＢＤＬ）行为，４５日龄幼鼠皮层、海马、小脑、脑桥和间脑等不同部位蛋白质含量及微量元素锌含量的变化。结果表明，此剂量的Ｂｅｓｔａｔｉｎ能明显抑制ＡＤＬ和ＢＤＬ行为，减少脑内尤其是海马内锌和蛋白质的含量。纳络酮有部分反转Ｂｅｓｔａｔｉｎ的作用。提示在出生后脑发育过程中，内源性的阿片肽可能通过影响海马内蛋白质的合成而参与分辨学习行为发育的调制。
Infant Spraque-Dawley rat pups were divided into three groups and received daily injection of saline,bestatin an aminopeptidase inhibitor,1 mg/kg(b.w) or naloxone 2 mg/kg(b.w) +bestatin 1 mg/kg(b.w) respectively from postnatal days 1-14. They were trained in the appetitive discrimination learning (ADL) at the age of 16 days,then in the bright discrimination learning of Y-maze (BDL) at 30 days of age. On postnatal days 45,the content of brain protein and zinc in cerebral cortex,hippocampus,cerebellum,pons,and diencephalon of the rats were examined. The results showed that the dose of bestatin inhibited significantly the learning behavior in ADL and BDL,and lowered the content of protein and zinc in hippocampus of the infant rats. Whereas,naloxone reversed partly the effect of bestatin. This suggested that the endogenous opiotide whould regulate some learning behavior through influncing synthesis of protein in hippocampus during postnatal brain development of infant rats.
