Bruce D S, Ambler D L, Henschel T M, Oeltgen P R, Nilekani S P, Amstrup S C
Biology Department, Wheaton College, IL 60187.
Pharmacol Biochem Behav. 1992 Sep;43(1):199-203. doi: 10.1016/0091-3057(92)90658-3.
Previous studies suggest that hibernation may be regulated by internal opioids and that the putative "hibernation induction trigger" (HIT) may itself be an opioid. This study examined the effect of plasma albumin (known to bind HIT) on induced contractility of the guinea pig ileum muscle strip. Morphine (400 nM) depressed contractility and 100 nM naloxone restored it. Ten milligrams of lyophilized plasma albumin fractions from hibernating ground squirrels, woodchucks, black bears, and polar bears produced similar inhibition, with partial reversal by naloxone. Five hundredths mg of D-Ala2-D-Leu5-enkephalin (DADLE) also inhibited contractility and naloxone reversed it. Conclusions are that hibernating individuals of these species contain an HIT substance that is opioid in nature and summer animals do not; an endogenous opioid similar to leu-enkephalin may be the HIT compound or give rise to it.
先前的研究表明，冬眠可能受内源性阿片类物质调控，且假定的“冬眠诱导触发因子”（HIT）本身可能就是一种阿片类物质。本研究检测了血浆白蛋白（已知可结合HIT）对豚鼠回肠肌条诱导收缩性的影响。吗啡（400 nM）可抑制收缩性，而100 nM纳洛酮可使其恢复。来自冬眠地松鼠、土拨鼠、黑熊和北极熊的10毫克冻干血浆白蛋白组分产生了类似的抑制作用，纳洛酮可部分逆转该作用。0.05毫克的D-丙氨酸2-D-亮氨酸5-脑啡肽（DADLE）也可抑制收缩性，纳洛酮可将其逆转。结论是，这些物种的冬眠个体含有一种本质上为阿片类物质的HIT物质，而夏季动物则没有；一种类似于亮氨酸脑啡肽的内源性阿片类物质可能就是HIT化合物或产生该化合物。
