Haller J, Albert I, Makara G B
Institute of Experimental Medicine, Hungarian Academy of Science, Hungary.
Behav Pharmacol. 1997 Jun;8(2-3):269-73.
Adult male Wistar rats were introduced into the home cage of residents accustomed to aggressive encounters. The attacks of the residents induced lasting immobility in the subjects. The alpha-2 adrenoceptor blocker idazoxan (which elicits an increase in brain norepinephrine release probably by the blockade of presynaptic autoreceptors) induced an enhancement of defeat-induced corticosterone secretion as well as a reduction in immobility. Pre-treatment with adrenocorticotrophin (ACTH) antiserum abolished both the increased adrenomedullar stress reaction and the reduction in immobility. It is concluded that norepinephrine-induced corticosterone secretion is involved in the immobility-lowering effects of alpha-2 adrenoceptor blockers. In previous experiments we have shown that the norepinephrine-induced increase in the aggressiveness of the residents depends on the ability to secrete corticosterone. Therefore it appears that the effects of norepinephrine on social conflict are at least partly mediated by corticosterone. This implies the involvement of acute corticosterone changes in fight/flight behaviours.
成年雄性Wistar大鼠被放入习惯攻击性遭遇的笼中居民的笼舍。居民的攻击导致受试动物出现持续不动状态。α-2肾上腺素能受体阻断剂咪唑克生（可能通过阻断突触前自身受体引起脑去甲肾上腺素释放增加）可增强失败诱导的皮质酮分泌，并减少不动状态。用促肾上腺皮质激素（ACTH）抗血清预处理可消除肾上腺髓质应激反应增强和不动状态减少这两种情况。得出的结论是，去甲肾上腺素诱导的皮质酮分泌参与了α-2肾上腺素能受体阻断剂降低不动状态的作用。在先前的实验中，我们已经表明，去甲肾上腺素诱导的笼中居民攻击性增加取决于分泌皮质酮的能力。因此，似乎去甲肾上腺素对社会冲突的影响至少部分是由皮质酮介导的。这意味着急性皮质酮变化参与了战斗/逃跑行为。
