Department of Biology, Philipps-University Marburg, Marburg, Germany.
Cryobiology. 2010 Apr;60(2):198-203. doi: 10.1016/j.cryobiol.2009.11.001. Epub 2009 Nov 12.
During entrance into torpor heart and respiration rates are greatly reduced in parallel with the reduction of metabolic rate, suggesting an involvement of parasympathetic control. We compared the effect of parasympathetic inhibition with the effect of sympathetic inhibition on spontaneous torpor behaviour in the Djungarian hamster. Hamsters were acclimated to short photoperiod and displayed their standard torpor pattern as observed from T(b) records. Parasympathetic inhibition was achieved by a subcutaneous implant of 21-day release pellets with Atropine and the sympathetic noradrenergic pathway was inhibited with a single injection of 6-Hydroxydopamine. Atropine treatment did not affect the occurrence and quality of spontaneous daily torpor at all. However, the reversible sympathetic inhibition by 6-Hydroxydopamine injection resulted in a complete disappearance of torpor for about 6 days. These results conclude that the onset of daily torpor requires an intact noradrenergic signalling of the sympathetic nervous system. We further observed that parasympathetic as well as sympathetic blockade resulted in an immediate abolishment of ultradian rhythms of body temperature. This suggests that the expression of ultradian oscillations in body temperature require a continued interaction of sympathetic and parasympathetic activity.
在进入蛰眠状态时，心率和呼吸率会与代谢率的降低成比例地大幅下降，这表明副交感神经控制的参与。我们比较了副交感神经抑制和交感神经抑制对达乌尔黄鼠自发蛰眠行为的影响。将仓鼠适应于短光照周期，并从 T(b)记录中观察到它们的标准蛰眠模式。通过皮下植入 21 天释放的阿托品丸来实现副交感神经抑制，并且通过单次注射 6-羟多巴胺来抑制交感去甲肾上腺素能途径。阿托品处理根本不影响自发每日蛰眠的发生和质量。然而，6-羟多巴胺注射的可逆性交感神经抑制导致大约 6 天的蛰眠完全消失。这些结果表明，每日蛰眠的开始需要完整的交感神经系统去甲肾上腺素信号。我们进一步观察到，副交感神经和交感神经阻断都会立即消除体温的超高频节奏。这表明，体温的超高频振荡的表达需要交感和副交感活动的持续相互作用。
