家兔心肌缺血时α_1-肾上腺素能受体的变化

The changes of α_1-adrenoceptor in ischeamic rabbit myocardium

本文用[~3H]-哌唑嗪为配基,测定了家兔心肌缺血前、心肌缺血后缺血区及非缺血区α_1-受体数目及亲和力的变化。发现家兔心肌缺血后15min缺血区α_1-受体明显增加,并持续到30min;45min时开始降低。非缺血区缺血前、后α_1-受体数目均无明显变化。α_1-受体亲和力在心肌缺血后缺血区和非缺血区均无显著变化。

We used (H^3)-prazosin on rabbits to determine the changes of α_1-adrenoceptor number (Bmax) and affinity (k_D) before and after ischemia, Within 15min of ischemia, we demonstrated that Bmax increased to twfold in ischeamic regions. The increase persisted for 30 min of ischemla and then began to fall at 45 min of ischemia. At the same time, in the nonischemic regions Bmax did not change. The results also showed that ischemia did not alter K_D markedly in both nonischeamic and ischeamic regions.