家兔^3H—cAMP颈内动脉注射后脑脊液放射活性的检测

在许多类型的发热过程中,血浆中cAMP含量都明显升高。但是否能通过血脑屏障进入中枢,从而介导发热,仍是一个有争议的问题。本实验经家兔颈内动脉注入~3H-cAMP,并用抗体结合法证明在开始注入后5、15及30分钟,有大量~3H-cAMP出现于脑脊液中;并以注射后5分钟含量最高,但此含量仍明显低于同时血浆中~3H-cAMP含量。此结果提示,至少在浓度较高的情况下,家兔血浆中的cAMP能有限制地通过血脑屏障而进入脑组织。

The examination of radioactivity in CSF after injecting ~3H-cAMP into internal carotid artery in rabbits

It has been found that cAMP concentration in plasma was significantly higher than its normal level in many kinds of fever. But, up to now, it has still been an indefinite problem, whether the cAMP in plasma can pass through the blood-brain barrier and get into central nervous system or not. In this experiment, after injecting ~3H-cAMP into the internal carotid artery of rabbits and using antibody-linking method, we found that ~3H-cAMP concentration in cerebral spinal fluid (CSF) increased significantly 5, 15 and 30 minutes after the beginning of the injection. The highest concentration of ~3H-cAMP in the CSF was in the five-minute sample but it was only half as high as that in the plasma in the same time. We suggested that it is possible that the cAMP in plasma passes through blood-brain barrier and gets into CSF by some way, but not freely.