Project description:We have used microarrays to comprehensively describe the transcriptomes of the supraoptic nucleus (SON), the paraventricular nucleus (PVN) and the neurointermediate lobe (NIL) of adult male Sprague-Dawley (SD) and Wistar-Kyoto (WKY) rats, as well as the paraventricular nucleus of Wistar (WIST) rats. Comparison of these gene lists has enabled us to identify surprisingly large differences in hypothalamo-neurohypophyseal system gene expression patterns in these three strains. We have also shown that different transcript populations are enriched in the PVN and the SON of SD and WKY rats. The transcriptome differences catalogued here may be molecular substrates for the neuro-humoral phenotypic differences exhibited by different strains of rats. Experiment Overall Design: For each experimental group (SON-WKY, PVN-WKY, NIL-WKY, SON-SD, PVN-SD, NIL-SD, PVN-WISTAR) five chips were hybridised with independantly pooled RNA from a biological n=5.
Project description:We have used microarrays to comprehensively describe the transcriptomes of the supraoptic nucleus (SON), the paraventricular nucleus (PVN) and the neurointermediate lobe (NIL) of adult male Sprague-Dawley (SD) and Wistar-Kyoto (WKY) rats, as well as the paraventricular nucleus of Wistar (WIST) rats. Comparison of these gene lists has enabled us to identify surprisingly large differences in hypothalamo-neurohypophyseal system gene expression patterns in these three strains. We have also shown that different transcript populations are enriched in the PVN and the SON of SD and WKY rats. The transcriptome differences catalogued here may be molecular substrates for the neuro-humoral phenotypic differences exhibited by different strains of rats. Keywords: Transcriptome, Hypothalamo-neurohypophyseal system, Genetic
Project description:To determine if there exists a consistent gene signature associated with vascular hypertrophy among different rat hypertensive models: treated and untreated Wistar Kyoto (WKY) rats and treated and untreated Spontaneous Hypertensive Rat (SHR) rats. Keywords: strain comparison, treatment vs control
Project description:The hypothalamic paraventricular (PVN) and supraoptic (SON) nuclei are important integrative structures that regulate co-ordinated responses to perturbations in cardiovascular homeostasis. Through descending projections from parvocellular neurons to the brainstem, the PVN acts as an autonomic 'premotor nucleus', regulating reflex changes in sympathetic nerve activity that are involved in blood pressure and blood volume regulation. Endocrine responses are mediated through axonal projections from SON and PVN magnocellular neurons (MCNs) to the capillaries of the posterior pituitary neural lobe. In response to dehydration, a massive release of the antidiuretic peptide hormone vasopressin (VP) into the circulation is accompanied by a dramatic functional remodelling of the HNS. We have used microarrays to comprehensively catalogue the genes expressed in the PVN, the SON and the neurointermediate lobe (NIL) of the pituitary gland. Further, we have identified transcripts that are regulated as a consequence of dehydration, as well as RNAs that are enriched in either the PVN or the SON. We suggest that these differentially expressed genes represent candidate regulators and effectors of HNS activity and remodelling. Keywords: DEHYDRATED - NIL
Project description:The objective of this study was to characterize differences in the global gene expression profiles of spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) at different stages of hypertension. Using RNA isolated from liver of SHR and WKY rats, we compared the gene expression profiles by microarrays. Differential gene expression was detected in the liver of SHR rats compared to WKY control rats, possibly contributing to hypertension
Project description:We have used Affymetrix microarray-driven gene profiling to comprehensively describe the expression of mRNAs in the nucleus tractus solitarii (NTS) in the adult male spontaneously hypertensive rat (SHR) as compared to its normotensive parental Wistar-Kyoto (WKY) strain. Keywords: Gene expression NTS was dissected from hypertensive (SHR) and normotensive (WKY) strains of rat. For each structure, 10 independent Affymetrix Genechip 230 2.0 experiments were performed (5 SHR, 5 WKY), with each chip representing an independent biological replication (n=5).
Project description:Analysis of global gene expression in mesenteric control and collateral arteries was used to investigate potential molecules, pathways and mechanisms responsible for impaired collateral growth in the Spontaneously Hypertensive rat (SHR). A fundamental difference was observed in the overall gene expression pattern in SHR vs. Wistar Kyoto (WKY) collaterals (only 6% of the genes altered in collaterals were similar). IPA analysis identified major differences between WKY and SHR in networks and biological functions related to cell growth and proliferation and gene expression. Canonical pathways identified by IPA in WKY but not SHR included nitric oxide and renin angiotensin system signaling. The angiotensin type 1 receptor (AT1R) exhibited up-regulation in WKY collaterals, but down-regulation in SHR; pharmacological blockade of the AT1R with losartan prevented collateral luminal expansion in WKY. In SHR control arteries, several mechano-sensitive and redox-dependent transcription regulators were down-regulated including Jun (-5.2X, P=0.02), Egr-1 (-4.1X, P=0.01), and NFkB1 (-1.95X, P=0.04). Predicted binding sites for NFkB and AP-1 were present in the genes altered in WKY but not SHR collaterals. Immunostaining demonstrated increased NFkB nuclear translocation in WKY but not SHR collaterals, and in collaterals of SHR treated with apocynin to restore a normal redox status. Based upon these results, we propose redox-dependent modulation of mechano-sensitive transcription factors as a mechanism to explain, at least in part, the fundamental differences in collateral gene expression between WKY and SHR and the impairment of collateral growth during chronic oxidative stress. Key words: arteriogenesis, microarray analysis, peripheral vascular disease, gene expression