内生致冷原对家兔内毒素性发热第二热相的影响

为验证内生致冷原(EC)能否影响内毒素(ET)性发热第二热相或热限水平,并确实脑脊液中cAMP水平是否与EC的降温作用有关,作者用90只新西兰兔进行实验。观察:①输注人尿或等量生理盐液对正常家免体温的影响,检测EC效应期血浆和脑脊液中cAMP的含量;②在第二热峰出现前输注人尿或生理盐液对第二热相的影响,检测EC效应期血浆及脑脊液中cAMP的含量。结果表明:①人尿明显降低正常家兔的直肠温度,而等量生理盐液则无此作用,且两者均引起血浆及脑脊液中cAMP浓度的明显下降,提示EC的降温作用与脑cAMP浓度下降可能无重要关系;②人尿(EC)抑制ET性发热第二热相的形成,从而降低热限水平,变双相热为单相热,同量生理盐水无此作用,两者都能降低血浆和脑脊液中cAMP的水平,但EC不及NS明显,表明EC抑制第二热相或降低热限水平的作用也与cAMP浓度变化无重要关系,作者推论cAMP不是ET性发热第二热相的唯一成因。

The effect of the endogenous cryogen on the second phase of rabbit endotoxin fever

In order to determine whether the endogenous crygen(EC)inhibits the second phase of ET-fever, the following observations were carried out: 1. Effect of the infusion of human urine on the body temperature of normal rabbits, changes of cAMP content in plasma and CSF during the EC active stage; 2. Effect of the infusion of human urine orequal volume of normal saline on the second phase of ET-fever, changes of the cAMP level in plasma and CSF during EC active stage. The results showed: 1. The rectal temperature of normal rabbits decreased markedly after human urine was given I. V., but not after normal saline I. V. The cAMP content in plsma and CSF decreased markedly after urine or saline was given. These findings indicated the cAMP level did not participate in the mechanism of the action of EC; 2. Formation of second phase of ET-fever was inhibited by urine infusion, level of hyperthermie ceiling also decreased and the biphasic fever was transformed to monophasic, but not by normal saline infusion. The cAMP content in plasma and CSF all decreascd after urine or saline I.V. infusion, but its effect on urine was not so significant as normal saline. These findings indicatd that inhibited action of EC was not related apparently to the cAMP level.