Dr. Ned J. Place

Department of Psychology

Dr. Place is a post-doctoral fellow working in Professor Irving Zucker's lab, where the principal areas of interest are the neuroendocrine bases of daily and seasonal rhythms. This research involves investigations into the reproductive biology of Siberian hamsters. Because Siberian hamsters are profoundly affected by photoperiod, and completely suppress reproductive function in response to short day lengths, Dr. Place uses this species as an animal model to study reproductive senescence. His research involves the manipulation of photoperiod and the pineal gland hormone melatonin to determine if reproductive aging can be decelerated by suppressing reproductive function at various life stages (e.g., before and after puberty). To date, these studies have shown that rearing in short day conditions improves reproductive success in animals mated at a relatively advanced age. Interestingly, the beneficial effects of short-day rearing on reproductive performance were not only lost when females underwent a pinealectomy at a very early age, the adverse effects of aging were amplified.

This research also showed that short-day reared females had a greater ovarian follicular reserve than females reared in long days, as evident by a significantly greater number of primordial follicles in the ovaries of short-day females. Since rearing in short days is associated with prolonged nighttime melatonin secretion and a spontaneous reduction in caloric intake, future studies are planned to assess the relative importance that these short-day responses have on reproductive aging. Understanding the mechanisms by which reproductive senescence is delayed in hamsters will be investigated at the molecular and cellular levels. This research may generate new ideas on how to decelerate reproductive aging in women. Moreover, because reproductive and somatic aging are so thoroughly intertwined, Dr. Place plans on completing longevity studies in hamsters, which will have important implications in the broader field of gerontology.