Analysis of thermoregulatory responses in the process of heat-and cold-acclimatization

冷热习服过程中的体温调节反应分析

基本信息

批准号：
60480122
负责人：
KOSAKA Mitsuo
金额：
$ 3.52万
依托单位：
Institute of Tropical Medicine, Nagasaki University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1985
资助国家：
日本
起止时间：
1985 至 1986
项目状态：
已结题

项目摘要

This study is performed to clarify the central and peripheral mechanism of thermal adaptation from the new concept of the extrahypothalamic deep body thermosenitivity. (1) The physiological changes that occur during heat acclimation were measured in six albino rabbits which had been reared at 30゜C (Ta) and 60% (RH) for 24 weeks continuously. During the experiment Ta was changed at a rate of 0.5゜C/min. The rectal temperature (Tre) change during Ta shift was 1.1 <+!-> 0.2 (Mean <+!-> SD) in the Heat acclimated rabbits compared to 1.6 <+!-> 0.3゜C in the control. The mean threshold level of Ta at which vasodilation of the ear began was 27.5 <+!-> 1.2゜C in the heat acclimated series compared to 25.0゜C in the controls. Conversely, vasoconstriction occured at 21.8 <+!-> 3.3゜C in the former compared to 14.7 <+!-> 2.9゜C in the later group. It is suggested that during heat acclimation there is a shift of the threshold temperature at which vasodilatation or vasoconstriction occurs. This is to pre … More vent changed of the core temperature. Further, under general anaesthesia (Nembutal 20mg/kg ip) there was no difference in the thresholds in the two series. It confirms that physiological changes in heat acclimation is through neuronal mechanisms influenced by anaesthesia sympathetic vasoconstrictor tones among the groups were measured after <IV> administration of adrenergic blocker (phentolamine mesylate 3mg/kg). At the same Te, there was greater vasodilation in the control than in the acclimated group, suggesting that vasoconstrictor tone is different between heat acclimated and non acclimated even at the same Ta. (2) In the present series of experiments, we tried to elucidate the nature of thermoregulation in responses to environ mental temperature shifts (25゜C 40゜C 10゜C 25゜C) in the rabbits devoid of pre-optic and anterior hypothalamic (PO/AH regions. Bilateral PO/AH lesions in male rabbits were accomplished using electrolytic procedure. And thermoregulator capabilities before and after PO/AH lesions were compared. In control rabbits, with the change in ambient temperature (Ta), the ear skin temperature (Tea) changed in the same direction. The change in rectal temperature (Tre) was small. In one-week-lesioned rabbit, the change of Tre was great when heated, but Tre was stable to cold stress. In two-weeks lesioned rabbit, Tre, inspite of Ta change, was quite stable: to the extent that it was comparable to the control rabbits. Therefore, these results should be interpreted as presenting the recovery of thermoregulatory functions after results should be interpreted as presenting the recovery of thermoregulatory functions after the PO/AH lesions. It is concluded that, without PO/AH participation, extrahypothalamic thermosenitive tissues were the places endowed with these thermorgulatory functions. Less

我进行的这项研究是为了澄清中央和周围的，是由外部丘脑外的深层体内剂量的热适应（1）在六个白化兔子中测量了发生热适应的生理变化。（RH）在经过0.5 c/min的速度上，几周在热适应的兔子中更改为0.5 c/min。埃根（Egan）在热适应序列中为27.5 <+！> 1.2 c c，而后来的组为25.0゜4.7<+！ - > 2.9 c c c。血管收缩发生。 <iv> adreneurgic阻滞剂（苯丙胺甲基酸盐3mg/kg）e TE，在控制中，血管收缩态在同一ta中即使在同一精神温度下的响应也不适应（25）。 c 40゜c 10゜c 25 c）使用PO/AH病变的兔子兔子的兔子中的兔子和雄性兔子的兔子兔病变对照兔子，皮肤温度（TEA）在同一方向上发生变化。：在与对照兔子相媲美的范围内，这些结果被解释为呈现温度调节的ult的恢复，应解释为呈现PO/AH病变后的温度调节功能。较少的。