冬眠麻酔時発現する「震え」に対する各種薬剤の効果について

STUDIES ON THE INHIBITORY EFFECTS OF THE MEDICINES ON THE SHIVERING BY COOLING

緒言

　近時，冷却あるいは薬剤により生体の代謝を低下せしめて，これを疾病の治療または手術の補助手段として利用しようとする所謂低体温麻酔が行われるようになつた。これにはSwan等^1）の物理的冷却法とLaborit^2）の自律神経遮断剤を併用する人為冬眠法とがあるが，何れも冷却によつて，体温がある程度下降すると，しばしば全身性の震えをきたすことが経験される。この震えに際しては，酸素消費量が増加し，基礎代謝率の上昇することが認められているが^3），このような症状は低体温麻酔の本来の目的からみて相反する併発症状とみなされている。

　そこで震えの防止策を講じようとして，当教室では平^4）が局所性震えについて，新川^5），高野^6），中出^7）が震えの中枢発現機序について，それぞれ追求してきたが，著者は震えを抑制させるような種々の薬物を投与して，その効果を比較検討し，震えの防止策をたてる上の資料を得ようとした。

Experiments were conducted on cats in or-der to investigate the inhibitory effects of medicines on the shivering elicited by the application of ice-bags on the body.

In this investigation not only the observati-on of the shivering with the naked-eye, but the discharge of the posterior hypothalamus (P. H. D.) and EMG's grouping voltage (G. V.) of the m. bicepus brachii were adapted as the indicate of shivering.

The medicines were given by injection th-rough a vein, but "Ether" was by inhalation.

1) As for "Ravonal", at the time of the disapearance of "Pinnareflex", when 8mg/kg it was given, not only did both shivering and G. V. vanish, but the spike of P. H. D.. This stituation continued for 40-50 minutes and the rectal temperature rose to no less than 25℃.

2) In case of inhalation of "Ether", shivering decreased gradually and G. V. also fell off in number, but its complete disappearance could be seen only after corneareflex had fallen off. But the spike-frequency of P. H. D. could hardly be seen changed in its apperance, besides, the recovery of shivering was corn-peratively quick and a low temperature also could not be attained as in the case when "Ravonal" was given.