Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0406810 (NAME)
 13,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The objective of this study was to design a methodology of gene transfer into a resistance vascular bed and to show if such a method can be used to examine the physiological function of a given gene product in vivo. We developed such a method and validated it by defining the role in vivo of endothelial nitric oxide synthase (eNOS). In a constant flow perfused rat hindlimb, gene transfer to the vascular endothelium was accomplished by incubating a "first-generation" serotype 5, replication-deficient, adenoviral vector (1.2 X 10(9) plaque-forming units/ml) containing cDNA encoding either the eNOS or the beta-galactosidase (beta-Gal) gene in the hindlimb vasculature for 30 min. Five days after infection, immunohistochemical staining for eNOS localized recombinant gene expression to vascular endothelial cells and eNOS protein levels were increased fourfold (11.9 +/- 6.6 vs. 2.9 +/- 1.3 intensity units/microg protein, n = 4, p < 0.05). Perfusion pressures were measured at different flow rates (10-50 ml/min). In addition, basal and acetylcholine (ACh)-stimulated vascular resistance (VR) in phenylephrine (PE)-precontracted (100 microM) hindlimb was measured at constant flow. There were flow-dependent increases (p < 0.05) in perfusion pressure. Overexpression of eNOS shifted the pressure-flow curve downward and administration of N(G)-nitro-L-arginine methyl ester (L-NAME) shifted the curve upward. Compared with beta-Gal-transfected rats, PE-induced VR decreased (p < 0.05) in eNOS-transfected rats (100 +/- 27 vs. 164 +/- 49 mmHg, n = 5). Addition of 100 microM L-NAME increased (p < 0.05) PE-induced VR in both eNOS-transfected and control rats (145 +/- 50 and 232 +/- 38 mmHg, n = 5, p < 0.05), respectively, which was partially abolished by L-arginine pretreatment. ACh-induced vasorelaxation was increased 45% (p < 0.05) in eNOS-transfected hindlimbs. L-NAME decreased (p < 0.05) ACh-induced vasorelaxation by 58% in eNOS-transfected hindlimbs versus 25% in beta-Gal-transfected hindlimbs (p < 0.05). We used this gene transfer method to examine the physiological function of a gene product in vivo and showed that (1) the flow-pressure relationship in the hindlimb vascular bed is NO dependent and (2) the eNOS enzyme modulates NO-mediated vasorelaxation in the rat hindlimb resistance arteries in vivo.
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PMID:Gene transfer of endothelial nitric oxide isoform decreases rat hindlimb vascular resistance in vivo. 1095 98

Administration of nitric oxide (NO) or NO donors to isolated carotid sinus and carotid bodies inhibits the activity of baroreceptor and chemoreceptor afferent nerves. Furthermore, NO synthase (NOS) is present in endothelial cells and in sensory nerves innervating the carotid sinus region. The major goal of this study was to determine whether overexpression of NOS in carotid sinus modulates baroreceptor activity. Rabbits were anesthetized, and adenoviral vectors (5 x 10(8) plaque-forming units) encoding genes for either beta-galactosidase (beta-Gal) or endothelial type III NOS (eNOS) were applied topically to the adventitial surface of one carotid sinus. In some experiments, the NOS inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME) was applied to the carotid sinus immediately after the vector. Four to five days later, baroreceptor activity and carotid sinus diameter were measured from the vascularly isolated carotid sinus of the anesthetized rabbits. Transgene expression was confirmed by X-Gal staining of beta-Gal and measurement of NOS activity by citrulline assay. The expression was restricted to the carotid sinus adventitia. Baroreceptor activity was decreased significantly, and the pressure-activity curve was shifted to higher pressures in eNOS-transduced (n = 5) compared with beta-Gal-transduced (n = 5) carotid sinuses. The pressure corresponding to 50% of maximum activity averaged 55 +/- 6 and 76 +/- 7 mmHg in beta-Gal- and eNOS-transduced carotid sinuses, respectively (P < 0.05). Decreased baroreceptor activity was accompanied by a significant increase in carotid diameter in the eNOS-transduced carotid sinuses (n = 5). l-NAME prevented the inhibition of baroreceptor activity and the increase in carotid diameter in eNOS-transduced carotid sinuses (n = 5). We conclude that adenoviral-mediated gene transfer of eNOS to carotid sinus adventitia causes sustained, NO-dependent inhibition of baroreceptor activity and resetting of the baroreceptor function curve to higher pressures.
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PMID:Modulation of baroreceptor activity by gene transfer of nitric oxide synthase to carotid sinus adventitia. 1267 43

Nitric oxide (NO) and endothelin-1 (ET-1) are known to play a major role in renal and vascular pathophysiology and exhibit a close interaction with ET-1, stimulating NO production; NO in turn inhibits ET-1 expression. Our objectives were (1) to establish a novel transgenic mouse model facilitating ET-1 expression assessment in vivo, (2) to validate this model by assessing prepro-ET-1 promoter activity in mice embryos by means of our novel model and comparing expression sites to well-established data on ET-1 in fetal development and (3) to investigate renal ET-NO interaction by assessing prepro-ET-1 promoter activity in different structures of the renal cortex in the setting of blocked NO synthases via L-NAME administration. We established transgenic mice carrying a lacZ reporter gene under control of the human prepro-ET-1 gene promoter sequence (8 kb of 5' sequences). Bluo-Gal staining of tissue sections revealed intracellular blue particles as indicators of prepro-ET-1 promoter activity. In mouse embryos, we detected high prepro-ET-1 promoter activity in the craniofacial region, as well as in bone and cartilage consistent with the literature. In order to investigate the interaction of ET-1 and NO in the kidney in vivo, transgenic mice at the age of 3-4 months were treated with a single dose of the NO synthase inhibitor L-NAME (25 mg (kg bw)(-1) i.p.) 12 h before kidney removal. Bluo-Gal staining of kidney sections revealed intracellular blue particles as indicators of prepro-ET-1 promoter activity in tubular and vascular endothelium and glomerular cells. Particle count was closely correlated to kidney tissue ET-1 content (R=0.918, P<0.001). Comparison of counts revealed an increase by 135+/-53% in L-NAME treated (n=12) compared to non-treated mice (n=10, P=0.001). Cell-type specific evaluation revealed an increase of 136+/-51% in tubular (P=0.001) and 105+/-41% in glomerular cells (P=0.046), but no significant increase in vascular endothelium. In conclusion, our study revealed a close interaction of renal endothelin and the NO system in a cell-type specific manner. Our new transgenic model provides a unique opportunity to analyse regulation of the ET system on a cellular level in vivo.
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PMID:Cell-type specific interaction of endothelin and the nitric oxide system: pattern of prepro-ET-1 expression in kidneys of L-NAME treated prepro-ET-1 promoter-lacZ-transgenic mice. 1739 29