%0 Journal Article
%T Nonsocial Functions of Hypothalamic Oxytocin
%A Hai-Peng Yang
%A Liwei Wang
%A Liqun Han
%A Stephani C. Wang
%J ISRN Neuroscience
%D 2013
%R 10.1155/2013/179272
%X Oxytocin (OXT) is a hypothalamic neuropeptide composed of nine amino acids. The functions of OXT cover a variety of social and nonsocial activity/behaviors. Therapeutic effects of OXT on aberrant social behaviors are attracting more attention, such as social memory, attachment, sexual behavior, maternal behavior, aggression, pair bonding, and trust. The nonsocial behaviors/functions of brain OXT have also received renewed attention, which covers brain development, reproduction, sex, endocrine, immune regulation, learning and memory, pain perception, energy balance, and almost all the functions of peripheral organ systems. Coordinating with brain OXT, locally produced OXT also involves the central and peripheral actions of OXT. Disorders in OXT secretion and functions can cause a series of aberrant social behaviors, such as depression, autism, and schizophrenia as well as disturbance of nonsocial behaviors/functions, such as anorexia, obesity, lactation failure, osteoporosis, diabetes, and carcinogenesis. As more and more OXT functions are identified, it is essential to provide a general view of OXT functions in order to explore the therapeutic potentials of OXT. In this review, we will focus on roles of hypothalamic OXT on central and peripheral nonsocial functions. 1. Introduction Recent progress in studying therapeutic potential of hypothalamic nonaneuropeptide oxytocin has resumed our enthusiasm of its classical physiological functions. In the hypothalamus, OXT is predominantly expressed in two types of neurons, that is, magnocellular neurons in the paraventricular (PVN) and supraoptic (SON) nuclei, and parvocellular neurons in the parvocellular division of the PVN. In magnocellular OXT neurons, OXT and its carrier, neurophysin I, are packaged in membrane-bound large dense-core vesicles and transported down the long axons to the nerve endings in the posterior pituitary or neurohypophysis [1]. In response to increased activity of OXT neurons, OXT is released from the neurohypophysis into the blood [2] to act on variety of peripheral tissues. The magnocellular neurons and the neurohypophysis that contain OXT and its partner peptide, vasopressin (VP, antidiuretic hormone) together form the hypothalamoneurohypophysial system. Lately, OXT is found to be released into other regions of brain [3¨C5], likely from the terminals of the OXT neurons of the parvocellular division of the PVN and axon collaterals and distal dendrites of magnocellular neurons [6]. In addition to the hypothalamic origin, OXT is also produced in extrahypothalamic regions and peripheral
%U http://www.hindawi.com/journals/isrn.neuroscience/2013/179272/