Mr Ben Saer (BSc, PhD) - personal details
I am a PhD student working with Prof Andrew Loudon and Dr Holly Shiels. Our interest is to look at the seasonal and metabolic role of thyroid hormone in the Siberian (Phodopus sungorus) and European hamster (Cricetus cricetus). Both species inhabit temperate regions and so are exposed to annual changes in photoperiod, ambient temperature and food availability. Consequently, this has driven a number of dramatic physiological changes to promote survival during periods of environmental adversity. These include body weight loss during the winter; pelage colour change from agouti to winter white; and testicular regression. Another such survival strategy during winter is torpor, which is a physiological state of controlled hypothermia and hypometabolism lasting hours to many days and is ended by arousal. There is now strong evidence to suggest that thyroid hormone is integral to seasonal physiology in P. sungorus, since application of T3 to hamsters promotes testicular growth and development of a summer coat, despite being maintained under winter-like conditions. My work has focussed on how the hypothalamic-pituitary thyroid axis is modulated between the seasons and comparing torpor with hibernation using in-situ hybridisation protocols, quantitative-PCR and immunohistochemistry.