低温时蛙皮素对 IL-1β致热大鼠下丘脑和血浆 cAMP含量的影响

目的: 以大鼠为实验对象建立发热动物模型,研究 4 ℃时蛙皮素的降温作用及其与 cAMP的关系。方法: 选择 SD雄性大鼠,4 ℃下侧脑室微量注射蛙皮素、白细胞介素-1β,观察大鼠体温变化情况,并测定下丘脑和血浆中 cAMP含量。结果: 在 IL-1β诱导发热大鼠中,下丘脑及血浆中 cAMP含量与对照组相比升高(P<0.01);蛙皮素可以降低大鼠正常体温,下丘脑 cAMP含量与对照组相比亦随之降低(P<0.01);预先侧脑室注射蛙皮素能翻转大鼠IL-1β性发热,且下丘脑 cAMP含量与 IL-1β组相比明显下降(P<0.01) 。结论: 4 ℃时蛙皮素能抑制IL-1β发热,其机制有可能是通过抑制 cAMP合成或释放实现的。

Effects of bombesin on cAMPcontent of hypothalamus and plasma in IL-1β-induced feverrats underlowertemperature

AIM: To study the effectsof bombesin on thermoregulation and its relationshiPwith camPcontent at 4 ℃.METHODS: Bombesin and IL-1βwere microin-jected into the lateral ventricles (LV) of male SD rats.Changes in colonic temperature and content of cAMPin hypothalamus and plasma were measured.RESULTS: (1) In the febrile rats induced by i.c.v.injection of IL-1β,content of cAMPin hypothalamus and plasma in-creased (P<0.01).(2) Bombesin could lowernormal body temperature in rats.Content of cAMPin hypothala-mus was lowerthan that in the control grouP(P<0.01).(3) Feverinduced by IL-1βwas reversed by pretreatment with bombesin,and content of cAMPin hypothalamuswas decreased compared with that in control grouP(P<0.01).CONCLUSION: Bombesin can inhibit IL-1β-in-duced feverat 4 ℃,and the mechanism may be related to the inhibition the synthesis and release of cAMP.