Ovariectomized ewes received unilateral infusions of 20 micrograms neuropeptide-Y (NPY) at a total of 13 intracerebral sites. Episodic secretion of luteinizing hormone (LH) was transiently suppressed on more than one occasion by daily infusions at a total of five intracerebral sites. Four of the effective sites were located within the third ventricle (two sites) and the rostral and ventral part...

Neuropeptide Y (NPY) is an abundant neuropeptide of the neocortex involved in numerous physiological and pathological processes. Because of the large electrophysiological, molecular, and morphological diversity of NPY-expressing neurons their precise identity remains unclear. To define distinct populations of NPY neurons we characterized, in acute slices of rat barrel cortex, 200 cortical neuro...

Intrahypothalamic (IHT) administration of neuropeptide Y (NPY) induces a robust feeding response in rats. We have shown previously that NPY-induced feeding is mediated by a pertussis-toxin-sensitive G protein in rats. NPY receptors are coupled to cAMP and Ca2+. Because these second messengers are known to activate cAMP response element binding proteins, (CREB), cAMP response element modulators,...

We have used human erythroleukemia (HEL) cells to investigate distal signaling mechanisms of neuropeptide-Y (NPY) receptors. NPY did not activate phospholipase D, determined as a phosphatidylethanol formation, or protein kinase C (PKC) determined enzymatically as a translocation to the plasma membrane. However, NPY caused a rapid (already maximal after 30 s) and concentration-dependent (maximum...

Much attention has been payed to tree shrews for their close phylogenetic relationship with primates, small size, and short reproductive cycle. Especially, they are considered as excellent experiential animals for medicine or/and disease research. A nucleotide sequence encoding neuropeptide Y(NPY) precursor has been cloned from the cDNA library of Tupaia belangeri chinensis. Sequence alignment ...

Neuropeptide Y is the ligand of a family of G-protein coupled receptors (Y(1) to Y(6)). In the thalamus, exogenous and endogenously released NPY can shorten the duration of thalamic oscillations in brain slices from P13 to P15 rats, an in vitro model of absence seizures. Here, we examine which Y receptors are involved in this modulation. Application of the Y(1) receptor agonist Leu(31)Pro(34)NP...

Neuropeptides are a promising target for novel treatments for anxiety and other psychiatric disorders and neuropeptide Y (NPY) has emerged as a key component of anxiolytic circuits in the brain. For this reason, we have evaluated the role of NPY in the expression and extinction of conditioned fear. We found that intracerebroventricular administration of NPY inhibits both baseline acoustic start...

BACKGROUND Sympathetic nervous system (SNS) signalling regulates murine hepatic fibrogenesis through effects on hepatic stellate cells (HSC), and obesity-related hypertension with SNS activation accelerates progression of non-alcoholic fatty liver disease (NAFLD), the commonest cause of chronic liver disease. NAFLD may lead to cirrhosis. The effects of the SNS neurotransmitters norepinephrine (...

There is evidence that neuropeptide Y (NPY) acts as a neurotransmitter in vascular smooth muscle and is released with norepinephrine from sympathetic nerves. We hypothesized that NPY Y(1) receptor stimulation would produce vasoconstriction in resting and exercising skeletal muscle. Nine mongrel dogs were instrumented chronically with flow probes on the external iliac arteries of both hindlimbs ...

In mammals, neuropeptide Y (NPY) is a potent orexigenic factor. In the present study, third brain ventricle (intracerebroventricular) injection of goldfish NPY (gNPY) caused a dose-dependent increase in food intake in goldfish, and intracerebroventricular administration of NPY Y1-receptor antagonist BIBP-3226 decreased food intake; the actions of gNPY were blocked by simultaneous injection of B...