9319525 Koike Neuropeptides act as chemical messengers in the brain and play vital roles in the physiology and behavior of a variety of species. Hormones of the vasopressin/oxtyocin superfamily has been shown to exist in may life forms including, molluscs, hydra and protozoan suggesting that gene duplication occurred in ancestors common to invertebrates and vertebrates. In vertebrates, including mammals, these hormones play a crucial role in reproduction, osmoregulation and cardiovascular function. Dr. Koike is interested in arginine vasotocin (AVT) and mesotocin, two members of this peptidergic system, that are found in domestic fowls. He has adopted the most sophisticated technology to examine the sites and regulation of the physiological expression of vasotocin in the brain and periphery. Dr. Koike will clone the receptor for this peptide and then examine the regulation of the AVT gene expression. He will influence the domestic fowl's physiology by a number of mechanisms including varying the availability of water injecting gonadal hormones, and determine how these changes affect the expression of the genes for AVT and its receptor. These studies will lead to a better understanding of the physiological roles of this family of hormones as neurotransmitters, as players in the reproductive systems and as regulators of cardiovascular function. Moreover, the findings will allow comparisons of the genes for AVT and its receptor in domestic fowl with homologous genes of other vertebrate classes and thus, will provide basic knowledge on the manner in which members of this hormone family and their functions have evolved. Finally, understanding the normal physiology of an economically and nutritionally important species will impact on the poultry industry which provides high quality protein at economical prices. ***
