冷适应可提高糖尿病大鼠的耐寒性。

Cold-acclimation improves cold-tolerance of diabetic rats.

Ferro J A, Macari M, Eizirik D L

Departamento de Tecnologia, Faculdade de Ciências Agrárias e Veterinárias, UNESP, Brazil.

Comp Biochem Physiol A Comp Physiol. 1987;88(3):425-9. doi: 10.1016/0300-9629(87)90057-0.

Abstract

The aim of these experiments was to study the extent to which previous cold-acclimation improves the cold-tolerance of diabetic rats. 2. Alloxan diabetic rats (fasting blood glucose higher than 200 mg/dl) were used in the experiments. 3. In Expt. 1, non-cold-acclimated control and diabetic rats were exposed to cold environment (7-9 degrees C), and the percentage of survival calculated during a 12-day experimental period. In Expt. 2, the rats were previously cold-acclimated before alloxan or saline injection (diabetic and control cold-acclimated rats) and the survival rate was also assessed during a 12-day period in the cold. 4. The percentage of survival of the non-cold-acclimated diabetic rats (Expt.1) was 19% compared with 79% of the diabetic cold-acclimated animals (Expt. 2). There were no deaths in the control groups. 5. Cold-acclimated diabetic rats maintained a near-normal thermogenic response after noradrenaline injection. This response was impaired in non-cold-acclimated diabetic rats. 6. The results of these experiments suggest that the enhanced cold-tolerance of diabetic cold-acclimated rats could be related to the increased sympathetic activity and enhanced insulin sensitivity in thermogenic tissues, such as brown fat.

摘要

这些实验的目的是研究先前的冷适应在多大程度上提高糖尿病大鼠的耐寒性。2. 实验中使用了四氧嘧啶糖尿病大鼠（空腹血糖高于200mg/dl）。3. 在实验1中，未进行冷适应的对照大鼠和糖尿病大鼠被置于寒冷环境（7 - 9摄氏度）中，并计算12天实验期内的存活率。在实验2中，大鼠在注射四氧嘧啶或生理盐水之前先进行冷适应（糖尿病和对照冷适应大鼠），并在寒冷环境中12天内评估存活率。4. 未进行冷适应的糖尿病大鼠（实验1）的存活率为19%，而冷适应的糖尿病动物（实验2）为79%。对照组无死亡情况。5. 冷适应的糖尿病大鼠在注射去甲肾上腺素后维持接近正常的产热反应。这种反应在未进行冷适应的糖尿病大鼠中受损。6. 这些实验结果表明，冷适应的糖尿病大鼠耐寒性增强可能与交感神经活动增加以及产热组织（如棕色脂肪）中胰岛素敏感性增强有关。