Many studies have implicated both angiotensin II (ANG II) and aldosterone (Aldo) in the pathogenesis of hypertension, the progression of renal injury, and cardiac remodeling after myocardial infarction. In several cases, ANG II and Aldo have been shown to have synergistic interactions in the periphery. In the present studies, we tested the hypothesis that ANG II and Aldo interact centrally in A...

In Wistar rats, increasing cerebrospinal fluid (CSF) Na+ concentration ([Na+]) by intracerebroventricular (ICV) infusion of hypertonic saline causes sympathetic hyperactivity and hypertension that can be prevented by blockade of brain mineralocorticoid receptors (MR). To assess the role of aldosterone produced locally in the brain in the activation of MR in the central nervous system (CNS), Wis...

Rats near term of pregnancy have an attenuated febrile response to intracerebroventricular (ICV) injection of prostaglandin E1 (PGE1) when they are studied at an ambient temperature below their thermoneutral zone. Given that nonshivering thermogenesis in brown adipose tissue is impaired in rodents near term of pregnancy, it is possible that the attenuated febrile response is forced by impairmen...

Central angiotensin II (ANG II) regulates thirst. Because thromboxane A2-prostaglandin H2 (TP) receptors are expressed in the brain and mediate some of the effects of ANG II in the vasculature, we investigated the hypothesis that TP receptors mediate the drinking response to intracerebroventricular (icv) injections of ANG II. Pretreatment with the specific TP-receptor antagonist ifetroban (Ifet...

For many procedures used in behavioral pharmacology, the intracerebroventricular (ICV) route of drug administration is infrequently used due, in part, to the lack of a reliable technique for determining cannula patency in vivo. This study describes an in vivo technique for assessing ICV cannula patency in pigeons. The technique was applied in an experiment designed to evaluate several drugs, wh...

BACKGROUND cAMP-dependent protein kinase (PKA) signaling pathways are involved in the regulation of ethanol-induced sedative effects in knockout mouse models. In the present study, we examined the role of PKA on the behavioral action caused by ethanol in Sprague Dawley rats. METHODS A loss of righting reflex (LORR) test was used to study the acute sedative effects of intraperitoneally injecte...

The intracerebroventricular (icv) application of streptozotocin (STZ) in low dosage was used in 3-month-old rats to explore brain insulin system dysfunction. Three months following STZ icv treatment, the expression of insulin-1 and -2 mRNA was significantly reduced to 11% in hippocampus and to 28% in frontoparietal cerebral cortex, respectively. Insulin receptor (IR) mRNA expression decreased s...

The accumulation and aggregation of misfolded proteins in the brain, such as amyloid-β (Aβ) and hyperphosphorylated tau, is a neuropathological hallmark of Alzheimer's disease (AD). Previously, we developed and validated a novel non-human primate model for sporadic AD (sAD) research using intracerebroventricular administration of streptozotocin (icv STZ). To date, no characterization of AD-rela...

Glucose intolerance in type 2 diabetes is related to enhanced hepatic glucose production (HGP) due to the increased expression of hepatic gluconeogenic enzymes. Previously, we revealed that hepatic STAT3 decreases the expression of hepatic gluconeogenic enzymes and suppresses HGP. Here, we show that increased plasma histidine results in hepatic STAT3 activation. Intravenous and intracerebrovent...

Automatic and accurate methods to estimate normalized regional brain volumes from MRI data are valuable tools which may help to obtain an objective diagnosis and followup of many neurological diseases. To estimate such regional brain volumes, the intracranial cavity volume (ICV) is often used for normalization. However, the high variability of brain shape and size due to normal intersubject var...