Kanwar K C, Chaudhry V
Endokrinologie. 1976 Jul;67(3):307-14.
The present work attempts to find out a relationship between testicular functions and thyroid activity in a seasonal breeder, Indian palm squirrel, Funambulus pennanti Wroughton. In addition to radioiodine studies used for assessing thyroid status during different months in the year, biochemical estimations and histological studies have also been undertaken with a view to determine thyroid and testicular functions. Testicular recrudescence in Indian palm squirrel starts in January and peak activity is reached during April and May. June marks the beginning of testicular regression and the maximal regression is reached in October. Fluctuations in thyroid function are clearly manifested by variations observed in radioiodine uptake during different phases of reproductive cycle. Cytoarchitecture of thyroid also changes somewhat during different periods of the year and these changes are in accordance with the results obtained from radioiodine uptake studies. The present investigation suggests that the thyroid has a definite and significant role to play during the period of testicular recrudescence and regression in seasonal breeder Funambulus pennanti and it seems to help in tapering off sexual arousal and regression rather than sudden switching on and off of the reproductive cycle. In addition, it seems to facilitate peak testicular activity. However, mechanisms whereby thyroid influences various testicular functions seem to involve a complex series of interactions.
本研究试图找出季节性繁殖者印度棕榈松鼠（Funambulus pennanti Wroughton）的睾丸功能与甲状腺活动之间的关系。除了利用放射性碘研究评估一年中不同月份的甲状腺状态外，还进行了生化测定和组织学研究，以确定甲状腺和睾丸的功能。印度棕榈松鼠的睾丸再发育始于1月，4月和5月达到活动高峰。6月标志着睾丸开始退化，10月达到最大退化程度。甲状腺功能的波动通过生殖周期不同阶段放射性碘摄取的变化明显表现出来。甲状腺的细胞结构在一年中的不同时期也会有所变化，这些变化与放射性碘摄取研究的结果一致。本研究表明，甲状腺在季节性繁殖者印度棕榈松鼠的睾丸再发育和退化期间具有明确且重要的作用，它似乎有助于逐渐减弱性唤起和退化，而不是突然开启和关闭生殖周期。此外，它似乎有助于促进睾丸的高峰活动。然而，甲状腺影响各种睾丸功能的机制似乎涉及一系列复杂的相互作用。
