Microinjection of glycine into the hypothalamic paraventricular nucleus produces diuresis, natriuresis, and inhibition of central sympathetic outflow.

Strychnine-sensitive glycine receptors and glycine-immunoreactive fibers are expressed in the hypothalamic paraventricular nucleus (PVN), yet the functional significance of this innervation is unclear. Therefore, these studies examined the changes in cardiovascular and renal function and renal sympathetic nerve activity (RSNA) produced by the microinjection of glycine (5 and 50 nmol) into the PVN of conscious Sprague-Dawley rats. Microinjection of glycine into, but not outside of, the PVN dose-dependently increased urine flow rate and urinary sodium excretion and decreased RSNA.

Tonic nociceptinergic inputs to neurons in the hypothalamic paraventricular nucleus contribute to sympathetic vasomotor tone and water and electrolyte homeostasis in conscious rats.

Central administration of nociceptin/orphanin FQ (N/OFQ) produces bradycardia, hypotension, diuresis, and antinatriuresis in rats. Because N/OFQ peptide (NOP) receptors exist in the paraventricular nucleus (PVN) of the hypothalamus, we hypothesized that N/OFQ acts in the PVN to alter cardiovascular and renal function. To test this premise, N/OFQ (10 and 100 pmol) or artificial cerebrospinal fluid (vehicle) was microinjected into the right PVN of conscious, chronically instrumented rats infused i.

Orexins in rat dorsal motor nucleus of the vagus potently stimulate gastric motor function.

Orexins regulate food intake, arousal, and the sleep-wake cycle. They are synthesized by neurons in the lateral hypothalamus and project to autonomic areas in the hindbrain. Orexin A applied to the dorsal surface of the medulla stimulates gastric acid secretion via a vagally mediated pathway.