The neurohypophysial hormones, arginine vasotocin and isotocin, regulate both hydromineral balance and social behaviors in fish. In the amphibious mudskipper, Periophthalmus modestus, we previously found arginine-vasotocin-specific regulation of aggressive behavior, including migration of the submissive subordinate into water. This migration also implies the need for adaptation to dehydration. ...

Ghrelin, a circulating growth hormone-releasing peptide derived from the stomach, stimulates food intake. The lowest systemically effective orexigenic dose of ghrelin was investigated and the resulting plasma ghrelin concentration was compared with that during fasting. The lowest dose of ghrelin that produced a significant stimulation of feeding after intraperitoneal injection was 1 nmol. The p...

In Persian traditional medicine is believed that camphor (a crystalline ketone obtained from cinnamomum camphora) is a suppressor of sexual behaviors. This study examined the central effects of camphor on sexual hormones (LH, FSH and testosterone) and GnRH plasma levels in male rat. Male Wistar rats weighing 250-260gr were selected and divided into control (no treatment), sham (ICV injection...

Ghrelin, an endogenous ligand for the GH secretagogue receptor 1a (GHS-R(1a)), was originally purified from the rat stomach. Ghrelin mRNA and peptide have also been detected in the hypothalamus and pituitary. Ghrelin is a novel acylated peptide that regulates GH release and energy metabolism. GHS-R(1a) mRNA is expressed in the pituitary gland as well as in several areas of the brain including t...

Thyrotropin-Releasing Hormone Precursor Gene Knocking Down Impedes Melanocortin-Induced Hypertension in Rats To the Editor: Recently, da Silva et al1 reported that endogenous melanocortin may cause elevation of arterial blood pressure (ABP) in spontaneously hypertensive rats. We invite authors to consider that the hypothalamic thyrotropin-releasing hormone (TRH) system may be involved, because ...

The contribution of the paraventricular nucleus of the hypothalamus (PVN) in mediating cardiovascular, renal, hormonal, and sympathetic nerve responses to increased cerebrospinal fluid (CSF) [Na(+)] was investigated in conscious sheep. Intracerebroventricular hypertonic NaCl (0.5 mol/l, 20 microl/min for 60 min) increased arterial blood pressure [AP; +13.4 (sd 2.0) mmHg, P < 0.001] and central ...

Hypothalamic orexin neurons project to the hindbrain, and 4th-ventricle intracerebroventricular (4th-icv) injection of orexin-A treatment increases food intake. We assessed the effects of hindbrain orexin-A and the orexin-1-receptor antagonist SB334867 on meal pattern in rats consuming standard chow. When injected 4th-icv shortly before dark onset, lower doses of orexin-A increased food intake ...

We recently demonstrated that in a rodent model of obesity (agouti yellow mice), there is a selective leptin resistance with preservation of the sympathetic actions despite loss of appetite and weight-reducing actions of systemic leptin. Here, we examined whether selective leptin resistance exists in agouti mice during central neural administration of leptin. In agouti obese mice and lean contr...

Objective(s): Growing evidence demonstrates that L-arginine/NO/cGMP/KATP channel pathway has a modulatory role in pain perception. Previous studies have shown that thymoquinone exerts antinociceptive effects; however, the mechanisms underlying antinociception induced by thymoquinone have not been fully clarified. The aim of the present study was to evaluate the role of L-arginine/NO/cGMP/KATP c...

glutamate as one of the most important neurotransmitter in the brain has a significant role in control of foodintake. this study examined the central effect of chicago sky blue 6b (csb6 ) as glutamate vesicular uptake inhibitor, on food and water intake in broilers. after icv injection of csb6 cumulative food and water intake were measured in 15,30,60,120 and 180 minutes. csb6 increased food in...