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-...

1. We studied the effects that lesions produced in the paraventricular and suprachiasmatic nuclei and intervening periventricular area had on 24 h mean circadian blood pressures in Dahl salt-sensitive and -resistant rats and their sham-operated controls. We measured blood pressures while the animals were on a low salt diet and after 1, 5 and 13 weeks of 8% NaCl diet. 2. Salt-sensitive rats with...

Angiotensin within the central nervous system appears to be important for the maintenance of hypertension in spontaneously hypertensive rats. This study addresses the hypothesis that blockade of AT1 receptors in the rostral ventrolateral medulla would decrease blood pressure in spontaneously hypertensive rats and that this tonically active AT1-mediated input to the rostral ventrolateral medulla...

The reductions in circulating levels of leptin, insulin, and glucose with fasting serve as important homeostasis signals to neurons of the hypothalamic arcuate nucleus that synthesize neuropeptide Y (NPY)/agouti-related protein (AGRP) and alpha-MSH/cocaine and amphetamine-regulated transcript. Because the central administration of leptin is capable of preventing the inhibitory effects of fastin...

Functional significance of neural projections from the hypothalamic dorsomedial nucleus (DMN) to the paraventricular nucleus (PVN) was investigated using surgical lesion of the central part of the DMN. Under basal conditions, DMN lesion resulted in a decrease in magnocellular vasopressin (AVP) mRNA levels in the PVN, rise in pituitary proopiomelancortin (POMC) mRNA concentrations and elevated p...

Signaling by the corticotropin-releasing factor receptor type 1 (CRFR1) plays an important role in mediating the autonomic response to stressful challenges. Multiple hypothalamic nuclei regulate sympathetic outflow. Although CRFR1 is highly expressed in the arcuate nucleus (Arc) of the hypothalamus, the identity of these neurons and the role of CRFR1 here are presently unknown. Our studies show...

In Huntington disease (HD), hypothalamic neuropeptidergic systems are not equally affected at the peptide and mRNA levels. Because prohormone convertases (PCs) are critically involved in the conversion of propeptides into their active forms, we postulated that a decrease in PC expression may underlie these discrepancies. Therefore, we assessed the expression of PC1/3 and PC2 in the hypothalamic...

Alcoholism can be viewed as a motivational disorder that results from alterations in brain systems for ingestive behavior. Therefore, it was hypothesized that alcohol intake might alter the expression of hypothalamic peptides that stimulate feeding. Earlier studies showed that hypothalamic injection of the feeding-stimulatory peptide, galanin (GAL), increases the release of dopamine (DA) in the...

When the hypothalamic ventromedial nucleus and arcuate nucleus were destroyed in rats by treatment with monosodium glutamate in the neonatal stage, increase in the Lee index (body weight 1/3/body length) and in retroperitoneal fat as well as decreases in spontaneous motor activity, food consumption and growth hormone secretion function associated with hypothalamic low body length obesity (monos...