Before concluding with some of the implications of holding that the physiological and behavioral extremes of hibernators are under especially adjustable neural controls (Chapter 8), the idea of rebalancing of existing regulatory mechanisms should be seen in the context of other examples of hypothalamic plasticity. This has been invoked on several occasions to account for changes occurring in non-hibernating mammals, especially those at puberty. Ramirez and McCann (1963) found that luteinizing hormone (LH) releasing factor is present in hypothalamic extracts even of immature rats, and that plasma LH rises following gonadectomy at this stage also.
KeywordsLuteinizing Hormone Lateral Hypothalamus Median Eminence Supraoptic Nucleus Luteinizing Hormone Secretion
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