环境温度对加压素引起大鼠低温反应的影响与棕色脂肪组织产热和理毛行为的关系

Effect of ambient temperature on arginine vasopressin-induced hypothermia in rats and its relationship with grooming behavior and brown adipose tissue thermogenesis

目的观察精氨酸加压素(AVP)引起正常大鼠低温反应与棕色脂肪组织温度(TBAT)和理毛行为变化的关系,以及不同环境温度对AVP引起低温反应的影响。方法用无线遥控测温技术连续同步记录成年雌性SD大鼠体核温度(Tc)、TBAT和动物活动的变化,观察腹腔注射AVP(10μg/kg)对Tc、TBAT和动物活动的影响。理毛行为是每隔10 min观察大鼠15 s内梳理皮毛的次数(次/15秒)作为观察指标。结果在25℃、30℃和18℃环境中,AVP均引起大鼠低温反应,但18℃环境中低温反应最明显。注射AVP后TBAT明显降低,理毛次数明显增加。结论 AVP引起的低温反应可能与体温调定点下移有关,因为在低温环境中AVP导致大鼠降温反应最明显,其机制与棕色脂肪组织产热减少和行为散热提高有关。

Objective To observe the effect of ambient temperature on arginine vasopressin（AVP）-induced hyperthermia of rats and its relationship with grooming behavior and brown adipose tissue（BAT）thermogenesis.Methods Core temperature（Tc）,motor activity and BAT temperature（TBAT）were monitored in adult female SD rats using radiotelemetry.Effect of AVP on Tc,motor activity and TBAT were observed at ambient temperature of 25℃,30℃ and 18℃,respectively.Grooming behavior was scored every 15s at 10 min intervals after AVP treatment.Results Administration of AVP led to an obvious hypothermia in rats at different ambient temperatures,But at ambient temperature of 18℃,Tc was lower than at 25℃ and 30℃.TBAT was significantly reduced and the grooming behavior was increased by AVP.Conclusion The effects of different ambient temperature on AVP-induced hypothermia in rats indicated that the hypothermic effects of AVP were mediated by an effect on temperature set-point,because AVP-induced hypothermic effect was greatest in the cold ambient temperature,and associated with inhibition of BAT thermogenesis and elevation of the behavioral thermoregulatory response.