Chen H J
Neurobiol Aging. 1981 Fall;2(3):215-9. doi: 10.1016/0197-4580(81)90024-5.
Effects of aging on estrous cycles and LH release in response to luteinizing hormone releasing hormone (LHRH), castration, and estradiol benzoate were studied in the female golden hamster (Mesocricetus auratus). About 80% to 90% of female golden hamsters still cycled regularly when reaching 19-22 months of age. However, some animals showed age-induced irregularity of the estrous cycle which included an interruption or complete absence of estrous vaginal discharge. Young female hamsters (3-5 months) had significantly (p less than 0.01) higher basal LH concentration than old animals (19-22 months) in the morning of each stage of estrous cycle. LHRH elicited about 20-30 fold increase in serum LH concentrations in both young and old hamsters. No significant difference in LH release was observed between young and old hamsters in response to LHRH. In acyclic hamsters, the peak of LH release in response to LHRH was delayed. LHRH-induced LH release was greater in the morning of proestrus than during diestrus in both young and old hamsters. LH increase was significantly greater in the young than in old hamsters on the 13th and 15th day after castration. However, positive feedback stimulation of LH release by estradiol benzoate was the same in both young and old hamsters. These results indicate that in the female hamster, LH response to acute stimuli such as LHRH and estrogens is the same in the young as in the old animal and that circulating basal LH concentration may decrease or its degradation or clearance may increase during the aging process in female golden hamsters. Irregularity of estrous cycles in aging hamsters may be related to delayed responsiveness of pituitary LH to LHRH stimulation.
在雌性金黄仓鼠（Mesocricetus auratus）中研究了衰老对发情周期以及促黄体生成素释放激素（LHRH）、去势和苯甲酸雌二醇刺激下促黄体生成素（LH）释放的影响。约80%至90%的雌性金黄仓鼠在19至22月龄时仍能正常发情。然而，一些动物出现了年龄诱导的发情周期不规则，包括发情期阴道分泌物中断或完全没有。在发情周期各阶段的早晨，年轻雌性仓鼠（3至5月龄）的基础LH浓度显著高于老年动物（19至22月龄）（p<0.01）。LHRH使年轻和老年仓鼠的血清LH浓度增加约20至30倍。在对LHRH的反应中，年轻和老年仓鼠的LH释放没有显著差异。在无发情周期的仓鼠中，对LHRH反应的LH释放峰值延迟。在年轻和老年仓鼠中，发情前期早晨LHRH诱导的LH释放均大于动情间期。去势后第13天和第15天，年轻仓鼠的LH增加显著大于老年仓鼠。然而，苯甲酸雌二醇对LH释放的正反馈刺激在年轻和老年仓鼠中是相同的。这些结果表明，在雌性仓鼠中，年轻动物和老年动物对LHRH和雌激素等急性刺激的LH反应相同，并且在雌性金黄仓鼠衰老过程中，循环基础LH浓度可能降低，或者其降解或清除可能增加。衰老仓鼠发情周期的不规则可能与垂体LH对LHRH刺激的反应延迟有关。
