Abstract

The neuroendocrine system has close interactions with the immune system. Their bidirectional communications emerged decades ago. On the one hand, there is a flow of information from the activated immune system to the hypothalamus. Antigenic stimulation changes the electrical activity of the hypothalamus and major endocrine responses; following thymectomy, hypothalamic cells degenerate extensively, appearing losses of nuclei or shrunk markedly. On the other hand, the autonomic nervous system and neuroendocrine outflow via the pituitary mediate brain modulation of immunologic activities. Thus, there is a neuroendocrine-immune network in the living organisms. In this network, the hypothalamus is the higher neuroendocrine center that regulates immunologic activities, and the target of immunologic activities. The immune-regulating ability of the hypothalamic center is represented by the hypothalamic-pituitaryadrenal (HPA) axis, the hypothalamic-pituitary-thyroid axis, and the hypothalamic-pituitary-gonad axis [1]. These axes function mainly through releasing Aden hypophysial hormones and are likely decisive in lymphoid cell homeostasis, self-tolerance, and pathology . Recently, critical roles of hypothalamic oxytocin-secreting system in immune regulation also become clear following the pioneer insight of Dr. Pittman . In this review, we further clarify how the oxytocin secreting system could be a major part of the neuroendocrine center that regulates immunologic activities.