Morin L P
Department of Psychiatry, SUNY, Stony Brook 11794.
Brain Res. 1992 Dec 18;599(1):98-104. doi: 10.1016/0006-8993(92)90856-5.
Intraventricular injections of the neurotoxin, 5,7-dihydroxytryptamine (DHT), were used to lesion hamster forebrain serotonin systems. The entrained circadian wheelrunning rhythm was studied for up to 20 weeks post-lesion as was the extent of reinnervation of nuclei regulating circadian rhythmicity. Reinnervation of the suprachiasmatic nucleus and intergeniculate leaflet by serotonergic fibers begins by 8 weeks and progresses to substantial, but not complete, levels by week 20. Four measures of the nocturnal activity phase of the circadian rhythm were rapidly modified by the lesions, but in contrast to the morphology, persisted unchanged during the entire 20 week test period. The circadian rhythm system of hamsters may be fundamentally different from other behavioral or neuroendocrine systems studied in rats with respect to its inability to recover from damage to its serotonergic innervation. Alternatively, the failure to demonstrate functional recovery may reflect a species difference or insufficient recovery time.
通过脑室内注射神经毒素5,7 - 二羟基色胺（DHT）来损伤仓鼠前脑的血清素系统。在损伤后的20周内，对夹带的昼夜节律性轮转行为进行了研究，同时也研究了调节昼夜节律的核团的再支配程度。血清素能纤维对视交叉上核和膝间小叶的再支配在8周时开始，并在第20周时进展到相当程度，但未完全恢复。损伤迅速改变了昼夜节律夜间活动阶段的四个指标，但与形态学变化不同的是，在整个20周的测试期内这些指标持续不变。仓鼠的昼夜节律系统可能与在大鼠中研究的其他行为或神经内分泌系统存在根本差异，因为它无法从血清素能神经支配的损伤中恢复。或者，未能证明功能恢复可能反映了物种差异或恢复时间不足。
