Acute studies have shown that MC3/4-R stimulation increases sympathetic activity, but the role of adrenergic activation in mediating the cardiovascular and renal responses to chronic melanocortin 3- and 4-receptor (MC3/4-R) activation is unknown. The present study tested whether chronic MC3/4-R activation raises blood pressure and whether these changes are attenuated by alpha1+beta-adrenergic b...

Increased hypothalamic neuropeptide-Y (NPY) action and disruption of the melanocortin (MC)-4 receptor both result in hyperphagia and obesity. To determine whether similar hormonal and metabolic mechanisms are involved in these two obesity syndromes, we investigated the time course of effects induced by 6-day intracerebroventricular (ICV) infusion of NPY (3.5 nmol/day) or the MC4 receptor antago...

Essential roles for gonadotropins in gonadal development and reproduction are well established. Over the past decade, however, the expression of luteinizing hormone receptor (LHR) has also been reported in the brain of various mammals and birds. Although suggestive, it has not yet been determined whether this expression pattern supports a novel function for gonadotropins. Here, we demonstrate a...

In neurodegeneration research, normalization of regional volumes by intracranial volume (ICV) is important to estimate the extent of disease-driven atrophy. There is little agreement as to whether raw volumes, volume-to-ICV fractions or regional volumes from which the ICV factor has been regressed out should be used for volumetric brain imaging studies. Using multiple regional cortical and subc...

In addition to the circulatory renin (REN)-angiotensin system (RAS), a tissue RAS having an important role in cardiovascular function also exists in the central nervous system. In the brain, angiotensinogen (AGT) is expressed in astrocytes and in some neurons important to cardiovascular control, but its functional role remains undefined. We generated a transgenic mouse encoding the human AGT (h...

OBJECTIVE We have previously found that chronic hypoxia inhibited thyrotropin-releasing hormone (TRH) mRNA expression in rat paraventricular nucleus (PVN). This study presented the effects of hypoxia on TRH secretion in rat hypothalamus, and the norepinephrine (NE) involvement in the modulation of TRH secretion during acute hypoxia exposure. SETTING AND DESIGN Hypoxia was simulated at altitud...

objective(s) the present study aimed to investigate the effects of a fat soluble antioxidant, coenzyme q10 (coq10) and folic acid on learning and memory in the rats with intracerebroventricular injection of streptozotocin (icv-stz), an animal model of sporadic type of alzheimer's disease. materials and methods the lesion groups were injected bilaterally with icv-stz (1.5 mg/kg b.wt., in no...

Besides other physiological functions, adenosine-5'-triphosphate (ATP) is also a neurotransmitter that acts on purinergic receptors. In spite of the presence of purinergic receptors in forebrain areas involved with fluid-electrolyte balance, the effect of ATP on water intake has not been investigated. Therefore, we studied the effects of intracerebroventricular (icv) injections of ATP (100, 200...

Background White matter hyperintensities (WMH) can be visualized as abnormal T2 signal in the periventricular, deep and subcortical white on Magnetic Resonance Imaging (MRI). WMH increase with age are associated stroke, cognitive decline dementia. The most common visual rating scale used to assess clinical setting is Fazekas (Fazekas et al., 1987). current study investigated relationship betwee...

Objective(s):Reduction of pharmacological effectiveness or tolerance appears following repeated administration of many analgesic drugs. We investigated tolerance to anti-nociceptive effects of orexin-A, an endogenous potent analgesic peptide using the hot-plate test.Materials and Methods:Orexin-A was microinjected ICV (intracerebroventricular) with an interval of 12 hr for 7 continuous days and...