The mammalian pineal gland receives information concerning the external environment via the nervous system and this is translated to the endocrine system. This function serves to coordinate the adaption of internal bodily response to the outside environment. The best known environmental signal received by the pineal gland is photoperiod. The pattern of daylight versus darkness characterizes the time of the year and predicts external, seasonal changes. Dr. Prechel has discovered a seasonal cycle of a neuropeptide in the pineal gland. This arginine vasotocin-like neuropeptide increases dramatically for a short time during mid-August each year in a number of species. Dr. Prechel will collect this peptide during August and then characterize and chemically identify it so that studies of its biological usefulness can proceed. In addition, she will determine how the animals "sense" when it is August by determining which component of our surroundings is capable of causing changes in hormones in the brain. An understanding of biological rhythms provides new insights into how humans adapt to changes in their external environment and will lead to the development of better treatments for problems such as jet lag, rotating work shifts and Seasonal Affective Disorder or "winter depression."
