The Effect of Swimming-Stress on Tail-Flick Latency of Normal and Hypophysectomized Rats

游泳刺激對正常及去垂體鼠閃尾潛伏期之影響

劉華茂(H. M. Liu)

《The Chinese Journal of Physiology》 29卷2期 (1986/12) Pp. 65-69

摘要

35隻大花鼠中之15隻爲正常鼠，10隻動假手術，10隻作垂體切除，將此等生理狀況不同之公鼠，輕放於閃尾致痛計上，以布片遮蓋其雙目，測定每隻老鼠當尾巴受高熱（約48℃）刺激後，直到感受疼痛而閃開其尾的時間，卽閃尾潛伏期(TFL)，兩次測定之間隔，必需相距3～5分鐘，自3～5次測試中取其平均值，卽爲當時之TFL，經過數次測定之後，卽讓同一隻老鼠接受3分鐘之游泳刺激及2分鐘之澈底乾拭，立即以游泳前之同一方式測取游泳後之TFL平均值，發現其值都比泳前者長，15隻正常對照組中之老鼠，其TFL延長1.34±0.28秒，假手術組延長1.27±0.2秒，去垂體鼠延長0.91±0.08秒，足證游泳刺激是可以抑制疼痛的，但去垂體鼠並不會改變游泳刺激所產生的止痛效應，因去垂體鼠在游泳後，其TFL仍然延長，此結果顯示游泳刺激所產生的止痛效應，與垂體之存在與否，並無顯著影響，此可能是因爲不同之刺激，導致中樞神經釋放不同之神經傳遞物質，游泳刺激之產生止痛效應，不一定與腦垂體之釋放類鴉片物質有關。

並列摘要

Liu, H.M.: The effect of swimming-stress on tail-flick latency on normal and hypophysectomized rats. Chinese J. Physiol. 29(2): 65-69, 1986: The effect of swimming-stress on pain threshold was investigated in normal and hypophysectomized male rats of Long-Evans strain. The Tail-Flick Latency (TFL) was taken for determining the algesic sensitivity to noxious heat stimulation of the tail.
The present study has shown that swimming-stress could prolong the TFL to thermal tail stimulation. In 15 intact control rats, the TFL were prolonged from 2.47±0.07 (Mean±S.E.) to 3.81±0.21 sec. In 10 sham-operated and 10 hypophysectomized rats, the TFL were also prolonged from 3.10±0.25 to 4.37±0.35 and 3.59±0.09 to 4.50±0.13 sec respectively after a 3 min swim. Therefore, the hypophysectomy did not appear to modulate the analgesic effect induced by swimming-stress.
These experimental data implied that the hypophysis may not be important in the analgesic effect induced by the swimming-stress.

並列關鍵字

Tail flick latency ； Swimming-stress ； Hypophysectomy