Comparative study of elgodipine and nisoldipine on the contractile responses of various isolated blood vessels

Chulia, Teresa; González, P.; Río, Marcela Del; Tejerina, Teresa

doi:10.1016/0014-2999(95)00374-t

Cited by 17 publications

(9 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Two stainless steel wires (φ = 40 μm) were threaded through the arteriole lumen, and the preparation [8,9]. Following an equilibration period of 20 min, the arterioles were set to a normalized internal circumference at which they gave the maximum isometric response.…”

Section: Isometric Myographymentioning

confidence: 99%

Dysfunction of human subcutaneous fat arterioles in obesity alone or obesity associated with Type 2 diabetes

Georgescu¹,

Popov²,

Constantin³

et al. 2011

Clinical Science

View full text Add to dashboard Cite

The aim of the present study was to examine the effects of obesity alone and obesity associated with Type 2 diabetes on the structure, vascular reactivity and response to insulin of isolated human subcutaneous fat arterioles; these effects were correlated with the expression of insulin signalling proteins. Periumbilical subcutaneous adipose tissue was explanted during surgery, small arterioles (internal diameter 220 ± 40 μm) were dissected out and investigated by electron microscopy, myography and immunoblotting. Compared with the subcutaneous arterioles of lean subjects, obesity activated the endothelium, enhanced the accumulation of collagen within vascular wall and increased the sensitivity of adrenergic response; obesity also diminished eNOS (endothelial NO synthase) protein expression, NO production, and endothelium-dependent and insulin-induced vasodilatation, as well as the protein expression of both IRS (insulin receptor substrates)-1 and IRS-2 and of the downstream molecules in the insulin signalling pathway, such as PI3K (phosphoinositide 3-kinase), phospho-Akt and Akt. When obesity was associated with Type 2 diabetes, these changes were significantly augmented. In conclusion, obesity alone or obesity associated with Type 2 diabetes alters human periumbilical adipose tissue arterioles in terms of structure, function and biochemsitry, including diminished eNOS expression and reduced levels of IRS-1, IRS-2, PI3K and Akt in the insulin signalling pathway.

show abstract

Section: Isometric Myographymentioning

confidence: 99%

Dysfunction of human subcutaneous fat arterioles in obesity alone or obesity associated with Type 2 diabetes

Georgescu¹,

Popov²,

Constantin³

et al. 2011

Clinical Science

View full text Add to dashboard Cite

show abstract

“…of the arteries used was in the range of 210-250 µm (resistance arteries). The myograph chamber was filled with HEPES salt solution (as described by Chulia et al 1995 andThurston et al 1995), maintained at 37°C and continuously gassed with O 2 . After an equilibration period of 20 min, the arteries were set to the normalized internal circumference (0.9 times the circumference they would have when relaxed and subjected to 100 mmHg).…”

Section: Experimental Animalsmentioning

confidence: 99%

Beneficial effects of L -arginine supplementation in experimental hyperlipemia-hyperglycemia in the hamster

Popov¹,

Costache²,

Georgescu³

et al. 2002

Cell and Tissue Research

View full text Add to dashboard Cite

The objective of this study was to evaluate whether administration of L-arginine, the substrate for nitric oxide synthesis, was able to ameliorate the endothelial dysfunction and the morphological changes induced by the combined insult of hyperlipemia and hyperglycemia. To this purpose, golden Syrian hamsters were rendered simultaneously hyperlipemic and diabetic (HD group) for 24 weeks, and then orally treated with 622.14 mg/kg per day L-arginine, for 12 weeks (HD + L-arg group). The following assays were carried out: (1) spectrophotometric: concentrations of circulating glucose, cholesterol, and creatinine, the activity of angiotensin-converting enzyme (ACE), and the osmotic fragility of erythrocyte plasmalemma; (2) myographic: the endothelium-dependent and -independent relaxation of the resistance arteries (i.d. 210-250 microm) to 10(-8) to 10(-4) M acetylcholine (ACh) or sodium nitroprusside (SNP); and (3) electron-microscopic: the ultrastructure of the resistance arteries, myocardium, and kidney glomeruli, which are main targets of hypertensive complications. The results showed that oral supplementation with L-arginine in simultaneous hyperlipemia-hyperglycemia induced in hamsters had favorable effects on: (1) homeostasis, i.e., diminished the concentration of circulating glucose (by ~63%) and cholesterol (by approximately 10%), reduced the ACE activity (by approximately 45%), and lowered the osmotic fragility of erythrocyte plasmalemma (as marker for the oxidative stress in plasma); (2) mesenteric resistance arteries, which showed (in 10(-4) M ACh) an improved endothelium-dependent relaxation (72.40+/-4.6% in the HD + L-arg group vs 61.90+/-1.45% in the HD group) and a reduced thickness (approximately 1.32-fold) of the smooth muscle cells' extracellular matrix; and (3) the heart, which displayed approximately 16% diminishing of the thickness of the left ventricular wall, and an apparently normal structure of the myocardium; the restoration of the thickness of the pericapillary extracellular matrix to almost normal dimensions was also observed. Administration of L-arginine did not modify the high level of plasma creatinine determined for the HD group (approximately 48% increased vs control group) and had no effect on the thickened, nodular basal lamina of the kidney capillaries. The results indicate that endothelial dysfunction established in combined hyperlipemia-diabetes is distinctive for each vascular bed (mesenteric arterioles, heart capillaries, kidney glomerular capillaries), and there is a reversible stage of the dysfunction in which L-arginine oral supplementation induced beneficial effects.

show abstract

“…To make sure that endothelium was completely removed, the inner side of the artery was gently rubbed with a stainless steel wire while mounting the vessel in the myograph [22] . The myograph chamber was filled with HEPES salt solution (HPSS) containing 5 mmol/l Hepes, 140 mmol/l NaCl, 4.6 mmol/l KCl, 1.17 mmol/l MgSO 4 , 2.5 mmol/l CaCl 2 , and 10 mmol/l glucose [23,24] maintained at 37 ° C and continuously gassed with O 2 . After an equilibration period of 20 min, the arteries were set to a normalized internal circumference at which they give a maximum isometric response and which is estimated to be 0.9 times the circumference they would have when relaxed and subjected to a transmural pressure of 100 mm Hg.…”

Section: Renal Artery Preparation For the Myograph Techniquementioning

confidence: 99%

Nebivolol Induces a Hyperpolarizing Effect on Smooth Muscle Cells in the Mouse Renal Artery by Activation of Beta-2-Adrenoceptors

et al. 2007

View full text Add to dashboard Cite

Nebivolol is a highly selective β₁-adrenoceptor antagonist with vasodilator properties involving the vascular endothelium, but its effect on the smooth muscle cells (SMC) is still unclear. In this paper, we tested the effect of nebivolol on renal artery smooth muscle cells and investigated the cellular mechanism involved. To this purpose, the denuded renal arteries isolated from mice were studied in vitro using the myograph and the nitric oxide (NO) sensor techniques, while the SMC in culture were analyzed by the patch-clamp technique. The myograph technique was used to assay the vasodilator effect of nebivolol on the arterial muscular layer, and to establish the optimal dose of the drug to be tested on single SMC by the patch-clamp technique. Using both the myograph and the patch-clamp techniques, we examined the potential contribution of β₂-adrenoceptors and Ca²⁺-activated K⁺ channels to the nebivolol-induced effects, by exposing the denuded arteries and SMC cultures to specific inhibitors such as butoxamine (100 µmol/l), tetraethylammonium (TEA, 1 mmol/l), and iberiotoxin (100 nmol/l). The direct measurement of NO using the NO sensor enabled us to evaluate if nebivolol induces/or not the release of NO in denuded renal arteries. The results of this study show that nebivolol exerts vasodilator effects on the SMC in the denuded renal arteries and the maximal response is achieved at a concentration of 50 µmol/l. Nebivolol effects involve binding to the β₂-adrenoceptors and the subsequent activation of Ca²⁺-activated K⁺ channels in SMC, with no contribution of NO. Taken together, the study brings new insights into the mechanism underlying the nebivolol-induced arterial vasodilation.

show abstract

Comparative study of elgodipine and nisoldipine on the contractile responses of various isolated blood vessels

Cited by 17 publications

References 26 publications

Dysfunction of human subcutaneous fat arterioles in obesity alone or obesity associated with Type 2 diabetes

Dysfunction of human subcutaneous fat arterioles in obesity alone or obesity associated with Type 2 diabetes

Beneficial effects of L -arginine supplementation in experimental hyperlipemia-hyperglycemia in the hamster

Nebivolol Induces a Hyperpolarizing Effect on Smooth Muscle Cells in the Mouse Renal Artery by Activation of Beta-2-Adrenoceptors

Contact Info

Product

Resources

About