PHOTOPERIODIC RESPONSIVENESS OF HAMSTERS WITH LESIONS OF THE LATERAL GENICULATE-NUCLEUS IS RELATED TO HIPPOCAMPAL DAMAGE
PHOTOPERIODIC RESPONSIVENESS OF HAMSTERS WITH LESIONS OF THE LATERAL GENICULATE-NUCLEUS IS RELATED TO HIPPOCAMPAL DAMAGE
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DOI：
10.1016/0361-9230(90)90204-d
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发表时间：
1990-02-01
影响因子：
3.8
通讯作者：
MORIN, LP
中科院分区：
文献类型：
--
作者：
SMALE, L;MORIN, LP
我们验证了下丘脑束在仓鼠光周期中起重要作用的假设。成年雄性仓鼠长时间光照（LD 14:10），接受外侧膝状核（LGN）大的双侧神经毒性病变或假病变。一周后，每组一半的动物被转移到短光期（LD 8:16），在那里他们维持了15周。大多数病变有效地破坏了膝间小叶（IGL）和大部分外侧膝状复合体。它们还会对上方的海马体造成严重损害。这种损伤对长时间的动物没有影响，但在短时间的光周期暴露中显著降低了睾丸退化的程度。然而，这种影响似乎是海马而非膝状神经损伤的结果。4个IGL完全损伤但海马损伤最小的个体，经历了与对照组难以区分的退化模式。白天短的动物体重增加，而白天长的动物则没有。这种效果与海马损伤程度无关。我们的结论是，对视交叉上核的膝状神经输入对仓鼠光周期并不是必需的，海马损伤可能会改变短日照对睾丸大小的影响。
We tested the hypothesis that the geniculohypothalamic tract is important for hamster photoperiodism. Adult male hamsters, maintained in a long photoperiod (LD 14:10), received either large bilateral neurotoxic lesions of the lateral geniculate nucleus (LGN) or sham lesions. One week later, half of the animals for each group were transferred to a short photoperiod (LD 8:16) where they were maintained for 15 weeks. Most lesions effectively destroyed the intergeniculate leaflet (IGL) and much of the lateral geniculate complex. They also caused substantial damage to the overlying hippocampus. The lesions had no effect on long-day animals, but significantly reduced the extent of testicular regression during short photoperiod exposure. This effect, however, appeared to be the result of hippocampal, rather than geniculate, damage. Four individuals with complete IGL lesions, but minimal hippocampal damage, underwent a pattern of regression that was indistinguishable from controls. Body weight was increased by lesions in short-day, but not long-day, animals. This effect was not related to the extent of hippocampal damage. We conclude that geniculate input to the suprachiasmatic nuclei is not essential for hamster photoperiodism and that hippocampal damage may modify the effect of short daylengths on testes size.