Vasopressin inhibits food intake in pygmy goats by activation of alpha 1-adrenergic receptors

Arginine vasopressin: Direct and indirect action on metabolism

From its identification and isolation in 1954, arginine vasopressin (AVP) has attracted attention, not only for its peripheral functions such as vasoconstriction and reabsorption of water from kidney, but also for its central effects. As there is now considerable evidence that AVP plays a crucial role in feeding behavior and energy balance, it has become a promising therapeutic target for treating obesity or other obesity-related metabolic disorders. However, the underlying mechanisms for AVP regulation of these central processes still remain largely unknown. In this review, we will provide a brief overview of the current knowledge concerning how AVP controls energy balance and feeding behavior, focusing on physiological aspects including the relationship between AVP, circadian rhythmicity, and glucocorticoids.

Oxytocin and Vasopressin Systems in Obesity and Metabolic Health: Mechanisms and Perspectives

PURPOSE OF REVIEW

The neurohypophysial endocrine system is identified here as a potential target for therapeutic interventions toward improving obesity-related metabolic dysfunction, given its coinciding pleiotropic effects on psychological, neurological and metabolic systems that are disrupted in obesity.

RECENT FINDINGS

Copeptin, the C-terminal portion of the precursor of arginine-vasopressin, is positively associated with body mass index and risk of type 2 diabetes. Plasma oxytocin is decreased in obesity and several other conditions of abnormal glucose homeostasis. Recent data also show non-classical tissues, such as myocytes, hepatocytes and β-cells, exhibit responses to oxytocin and vasopressin receptor binding that may contribute to alterations in metabolic function. The modulation of anorexigenic and orexigenic pathways appears to be the dominant mechanism underlying the effects of oxytocin and vasopressin on body weight regulation; however, there are apparent limitations associated with their use in direct pharmacological applications. A clearer picture of their wider physiological effects is needed before either system can be considered for therapeutic use.

Attenuation of the anorectic effects of glucagon, cholecystokinin, and bombesin by the amylin receptor antagonist CGRP(8-37)

The anorectic effect of IP injection of amylin (1 microgram/kg) was abolished by simultaneous IP injection of the amylin receptor antagonist calcitonin gene-related peptide-(8-37) [CGRP(8-37), 10 micrograms/kg]. The IP injection of pancreatic glucagon (400 micrograms/kg) at dark onset also reduced food intake in 24-h food-deprived rats, and this effect was also totally blocked by coadministration of CGRP(8-37) (10 micrograms/kg). In another feeding paradigm with glucagon (540 micrograms/kg IP 3 h into the light phase in 3 h-prefed rats), however, the anorectic effect of glucagon was not significantly antagonized by CGRP(8-37). The anorectic effect of cholecystokinin (CCK) (0.25 microgram/kg) and bombesin (BBS) (2 micrograms/kg) was partly neutralized by CGRP(8-37). In contrast, the anorectic effect of vasopressin (VP) (2.5 micrograms/kg) was not influenced by CGRP(8-37). As glucagon has been shown previously to increase the secretion of amylin, we conclude that the anorectic effect of peripherally administered glucagon is mediated by the release of amylin, at least under certain conditions. This may also be true for CCK and BBS, as these peptides are insulinotropic and may therefore be presumed to increase amylin release.