Reptilian Thyroid Physiology

本项目旨在研究甲状腺激素在调节爬行动物有氧能量能力以维持运动活动中的作用。由于哺乳动物和鸟类的恒温动物是沿着爬行动物祖先的基本平行线独立进化的，这些关于爬行动物的研究可能会提供关于甲状腺激素在导致现代恒温动物的祖先条件下的非体温调节作用的见解。将进行三个互补的研究方向。首先，分析甲状腺激素总量和游离水平的自然季节周期以及相关生理和行为因素的变化，为实验工作提供解释框架。其次，实验室实验将采用新的方法来诱导甲状腺激素水平在调节特定过程中的生理改变。第三，将进行实地实验，以调节野外活动蜥蜴的甲状腺激素水平，并测试季节性激素周期在调节特定过程中的作用。该研究有望获得甲状腺激素对支持活动的生理过程的调节的新信息，并可能有助于阐明这些过程与自然活动相关的适应性意义。

This project proposes to examine the involvement of thyroid hormones in regulating aerobic energetic capacities to sustain locomotor activity in reptiles. As endothermy evolved independently in mammals and birds along essentially parallel lines of reptilian ancestry, these studies on extent reptiles may provide insight into non-thermoregulatory roles of thyroid hormones in the ancestral conditions that led to modern endotherms. Three complementary lines of research will be conducted. Firstly, natural seasonal cycles in total and free levels of thyroid hormones and correlated changes in physiological and behavioral factors will be analyzed to provide the interpretational framework for experimental work. Secondly, laboratory experiments will employ new methods to induce physiological alterations in levels of thyroid hormones in regulating particular processes. Thirdly, field experiments will be done to regulate levels of thyroid hormones in field-active lizards and to test the involvement of seasonal hormone cycles in regulating particular processes. The research is expected to yield new information on the regulation by thyroid hormones of physiological processes that support activity and may help to clarify the adaptive significance of these processes in relation to natural activity.