兔回肠纵肌肾上腺素能爱体作用分析及递质间的相互作用

Effects of adrenoreceptor and interaction of norepinephrine and acetylcholine on the contraction of longitudinal muscle of rabit ileum in vitro

实验采用兔离休回肠纵肌标本，观察了经典递质去甲肾上腺素（ＮＥ．）和乙酰胆碱（ＡＣｈ．）对兔回肠纵肌收缩的效应及其相互关系，并对其作用的受体途径进行了分析．实验结果表明；（１）ＡＣｈ能加强回肠纵肌收缩，ＮＥ有抑制作用，但二者的作用可以变化；（２）酚妥拉明使收缩力量增加，心得安使其减弱；（３）ＮＥ能加强Ａｃｈ的兴奋作用，这一加强作用可放心得安阻断．ＡＣｈ对ＮＥ的抑制作用无明显影响．以上结果提示，兔回肠纵肌α肾上腺素能受体介导抑制，β受体介导兴奋，ＮＥ加强Ａｃｈ的兴奋效应与β受体密切相关．

The purpose of this study is to observe the effects of norepinephrine (NE) and acetylcholine (Ach) on the contraction of isolated rabit ileum logitudinal muscle and the in teraction between the two and to analyse its mechanism. The results are as follows: (1) The contraction is enhanced by Ach and inhibited by NE. (2) Phentolamine could enhance the contraction and propranolol could reduce. (3) The excitatory effect of Ach could be in creased by NE, but the effect could be blocked by propranolol. Ach does not have any effect on the inhibition of NE. The results suggest that: α-adrenoreceptors, which are present on the ileum longitudinal muscle of rabit, mediate inhibition; β-adrenoreceptors mediate excitation, the NE increases the excitatory responses of Ach Via β-adrenoreceptor.