Central Neuroendocrine Control of the Cardiovascular System

Abstract

The paraventricular nucleus (PVN) is a pivotal central structure involved in neuroendocrine cardiovascular regulation. The main PVN effects on blood pressure are exerted through modulation and integration of its neuroendocrine and autonomic functionally segregated parts. Neuroendocrine PVN activity is conveyed by magnocellular neurons (MCNs) and some portion of parvocellular neurons (PCNs). MCNs are the main source of vasopressin (VP) and oxytocin (OT), neuropeptides that show both endocrine and neuromodulatory activity. In the blood, VP reabsorbs water, vasoconstricts most vascular beds and increases the sensitivity of the baroreflex, whereas OT enhances natriuretic peptide release and natriuresis, displays cardioprotection and rather inconsistent effects on vasculature. Some PCNs possess secretory capacity and are responsible for the synthesis of corticotropin-releasing hormone (CRH), which dictates glucocorticoid blood levels and the stress response. Separate pool of PCNs projects to medulla and spinal cord affecting the sympathetic outflow to cardiorenal system and baroreflex function, as part of the PVN-mediated autonomic control. These PCNs are inhibited under baseline conditions by surrounding GABA interneurons and disinhibited during stress, exercise, and diseases. Notably, VP is also released from dendrites and somata of MCNs into the extracellular space, where it exhibits autocrine control and paracrine integration of neuroendocrine and autonomic responses to complex challenges. Being a highly dynamic structure, the PVN converges various inputs, mainly those related to the osmotic and cardiovascular status of the body, as well as stress, reacting in a sex-specific manner. When activation of PVN neurons is prolonged, it has detrimental effects that culminate in cardiovascular disorders, such as hypertension and heart failure (HF). © The Author(s), under exclusive license to Springer Nature Switzerland AG 2023.