Nelson E, Panksepp J, Ikemoto S
Department of Psychology, Bowling Green State University, OH 43403.
Pharmacol Biochem Behav. 1994 Oct;49(2):327-33. doi: 10.1016/0091-3057(94)90429-4.
Melatonin (0.1-1.0 mg/kg) reduced isolation-induced distress vocalizations (DVs) in young domestic chickens in a dose-dependent manner. This effect was unaffected by the administration of d-amphetamine (1.0 mg/kg) suggesting that melatonin's effects were not merely due to fatigue. The melatonin reduction in DVs was not naloxone reversible, indicating an action independent of the endogenous opioid system. However, chronic pretreatment with naltrexone facilitated the melatonin effect, suggesting a complex relationship between melatonin and the endogenous opioids in regulating distress vocalizations. Chickens exhibited a marked reduction in DVs when isolation chambers were darkened, suggesting endogenous, as well as exogenous, melatonin mediation of isolation distress; however; pinealectomy only partially reversed the darkness effect. Pinealectomized animals, like control animals, exhibited a reduction in DVs following melatonin treatment; however, the melatonin effect was shorter lasting. The implications that these results may have for socialization and emotional distress are discussed.
褪黑素（0.1 - 1.0毫克/千克）以剂量依赖的方式减少了幼年家鸡因隔离引起的痛苦叫声（DVs）。这种效应不受d - 苯丙胺（1.0毫克/千克）给药的影响，这表明褪黑素的作用不仅仅是由于疲劳。褪黑素对DVs的减少作用不能被纳洛酮逆转，这表明其作用独立于内源性阿片系统。然而，用纳曲酮进行慢性预处理促进了褪黑素的作用，这表明褪黑素与内源性阿片类物质在调节痛苦叫声方面存在复杂的关系。当隔离室变暗时，家鸡的DVs显著减少，这表明内源性以及外源性褪黑素都参与了隔离痛苦的调节；然而，松果体切除仅部分逆转了黑暗效应。松果体切除的动物与对照动物一样，在接受褪黑素治疗后DVs减少；然而，褪黑素的作用持续时间较短。本文讨论了这些结果可能对社交和情绪困扰产生的影响。
