Neuropeptide Y (NPY) is released from an extensive network of postganglionic sympathetic perivascular neurons. NPY has been shown to affect vascular tone postsynaptically by 1) directly stimulating contraction; 2) inhibiting vasorelaxation; and 3) potentiating contraction elicited by exogenous vasoconstrictors. The molecular mechanisms mediating these effects of NPY are undefined. Therefore, we...

Effects of neuropeptide Y (NPY) on motility of the proximal stomach was examined in anesthetized rats. Intragastric pressure was measured using a balloon situated in the proximal part of the stomach. Administration of NPY into the fourth ventricle induced relaxation of the proximal stomach in a dose-dependent manner. Administration of an Y1 receptor (Y1R) agonist [Leu31, Pro34]NPY induced a lar...

Exposure of chicks to a high ambient temperature (HT) has previously been shown to increase neuropeptide Y (NPY) mRNA expression in the brain. Furthermore, it was found that NPY has anti-stress functions in heat-exposed fasted chicks. The aim of the study was to reveal the role of central administration of NPY on thermotolerance ability and the induction of heat-shock protein (HSP) and NPY sub-...

Neuropeptide Y (NPY) plays a key role in both food intake and GnRH secretion. Food deprivation elevates hypothalamic NPY activity and suppresses LH and gonadal steroid secretion. Similarly, lactation up-regulates NPY expression as food consumption increases and estrous cycles cease. These observations suggest that NPY coordinates reproductive suppression in response to energy deficiency; if so,...

Neuropeptide Y (NPY) is one of the important endogenous orexigenic peptides. In these studies we employed c-Fos immunostaining and a selective NPY Y1 receptor antagonist to identify the site of action of NPY in the hypothalamus. The results showed that intracerebroventricular administration of NPY stimulated feeding and increased immunostaining of c-Fos, a product of the immediate early gene c-...

A number of studies have indicated that neuropeptide Y (NPY) is a central regulator of the gonadotropic axis, and the Y1 receptor was initially suggested to be implicated. As at least five different NPY receptor subtypes have now been characterized, the aim of the present study was to reinvestigate the pharmacological profile of the receptor(s) mediating the inhibitory action of NPY on LH secre...

Background Neuropeptide Y (NPY) is a 36-amino-acid peptide that is abundantly expressed in the central nervous system. It is involved in various physiological and pathophysiological processes, including energy homeostasis, pain and epilepsy, but also in anxiety and depression. Consistent findings have demonstrated an anxiolytic effect of NPY. The presence of different NPY receptors in the amygd...

The developmental increase in L-type Ca current ( I Ca,L) density in the rat ventricle is reproduced in vitro by culturing neonatal myocytes with sympathetic neurons. We tested whether this effect of sympathetic innervation results from a chronic or sustained action of neurally released neuropeptide Y (NPY). Ventricular myocytes from newborn rats were cultured in serum-free medium with or witho...

Two types of binding sites have previously been described for 36-amino acid neuropeptide Y (NPY), called Y1 and Y2 receptors. Y2 receptors can bind long C-terminal fragments of NPY-e.g., NPY-(13-36)-peptide. In contrast, Y1 receptors have until now only been characterized as NPY receptors that do not bind such fragments. In the present study an NPY analog is presented, [Leu31, Pro34]NPY, which ...