Hastings M H, Roberts A C, Herbert J
Neuroendocrinology. 1985 Apr;40(4):316-24. doi: 10.1159/000124093.
This paper presents evidence which demonstrates that a site within the anterior hypothalamus of the Syrian hamster is essential for the expression of a photoperiodic response but not for the expression of oestrous or circadian activity rhythms. Selective lesions of the anterior hypothalamic nucleus (AHN) were produced by localized infusions of n-methyl aspartic acid (NMA). Histological analysis revealed that the suprachiasmatic and paraventricular nuclei were resistant to the toxin. Circadian locomotor activity rhythms and oestrous cyclicity were unaffected by these lesions but the photoperiodic response of the gonads to short day length (8L:16D) was completely prevented. In marked contrast to control animals, lesioned animals maintained large testes or ovulatory ovaries, even after 10 weeks of exposure to the inhibitory photoperiod. These data suggest that neurones within the AHN form an essential component of the photoperiod time-measuring apparatus which is independent of that controlling circadian rhythmicity.
本文提供的证据表明，叙利亚仓鼠下丘脑前部的一个位点对于光周期反应的表达至关重要，但对于发情或昼夜活动节律的表达并非如此。通过局部注入N-甲基天冬氨酸（NMA）对下丘脑前核（AHN）进行选择性损伤。组织学分析显示，视交叉上核和室旁核对该毒素具有抗性。这些损伤并未影响昼夜运动活动节律和发情周期，但性腺对短日照（8小时光照：16小时黑暗）的光周期反应被完全阻断。与对照动物形成鲜明对比的是，即使在暴露于抑制性光周期10周后，受损动物仍维持着较大的睾丸或排卵卵巢。这些数据表明，AHN内的神经元构成了光周期计时装置的一个重要组成部分，该装置独立于控制昼夜节律性的装置。
