Model Roles of the Hypothalamo-Neurohypophysial System in Neuroscience Study

Dan Hou,Feng Jin

doi:10.4172/2167-0501.1000211

Abstract

Studies on the Hypothalamo-Neurohypophysial System (HNS) have played a pivotal role in establishing the fundamental principles of neuroscience. Examples include the identification of excitation-secretion coupling, coexistence of peptides-containing large dense core vesicles with classical neurotransmitters, neuronal-glial interactions, functionsassociated morphological plasticity, and domain-specific regulation of the secretory activity, etc. Moreover, mechanisms underlying the secretion by the HNS and functions of neuropeptides oxytocin and vasopressin remain the central topic of the neuroendocrine society, novel findings of which keep substantiating the model role of this system. Nevertheless, challenges are still severe in this study field, such as extrahypothalamic connections of the HNS, scaffolding and guiding roles of glial fibrillary acidic protein in astrocyte plasticity, cellular and molecular processes determining different firing patterns, the position of the HNS in neuroendocrine-immune network, and the nose-hypothalamic route that serves as a key mediator of drug effects on brain activity. Nowadays, translational studies of the HNS also become the prime time of researchers, such as vasopressin involvement in brain injury in ischemic stroke, and therapeutic potentials of oxytocin in lactation failure and its associated health issues. In this paper, we review these challenges in modern neuroscience studies on the HNS.

Highlights

In the hypothalamus, there are two types of peptidergic magnocellular neurosecretory cells (MNCs): oxytocin (OXT)producing neurons and vasopressin (VP)-producing neurons
From functional studies of circulating nonapeptides that extensively modulate the activities of almost all organ systems, to their brain actions that are represented by the autocrine regulation and prosocial effects, and to the hidden secretion of peripherally produced OXT and VP that subtly adjust the activities of individual cells, studies on the Hypothalamo-Neurohypophysial System (HNS) have been playing a pivotal role in establishing the fundamental principles of the neuroscience and the working models of neuropeptides
Together with the proposal by Pittman [104], we propose that in the neuroendocrine-immune network, the HNS can integrate immunologic, neural signal, and hormonal messages and regulate immunologic activities directly as well as indirectly through the HPA axis (Figure 4)

Summary

Introduction

There are two types of peptidergic magnocellular neurosecretory cells (MNCs): oxytocin (OXT)producing neurons and vasopressin (VP)-producing neurons. Studies on the SON have greatly contributed to the concepts of the excitation-secretion coupling, neuronal-glial interactions, functions-associated morphological plasticity, and domain-specific regulation of the secretory activity, etc.

Results

Conclusion