Publications by authors named "Belen Cortina"

Aim: To evaluate the effects of asymmetric dimethylarginine (ADMA) in renal arteries from portal hypertensive and cirrhotic rats.

Methods: Rat renal arteries from Sham ( = 15), pre-hepatic portal hypertension (PPVL; = 15) and bile duct ligation and excision-induced cirrhosis (BDL; = 15) were precontracted with norepinephrine, and additional contractions were induced with ADMA (10-10 mol/L), an endogenous inhibitor of nitric oxide (NO) synthase. Concentration-response curves to acetylcholine (1 × 10-3 × 10 mol/L) were determined in precontracted renal artery segments with norepinephrine in the absence and in the presence of ADMA.

View Article and Find Full Text PDF

We tested the hypothesis that the phytoestrogen genistein protects the brain against ischemic stroke by improving the circulatory function in terms of reduced production of thromboxane A2 and leukocyte-platelet aggregates, and of preserved vascular reactivity. Ischemia-reperfusion (90 min-3 days, intraluminal filament) was induced in male Wistar rats, and functional score and cerebral infarct volume were the end points examined. Genistein (10mg/kg/day) or vehicle (β-cyclodextrin) was administered at 30 min after ischemia or sham-operation.

View Article and Find Full Text PDF

Background And Aim: Increased basal release of nitric oxide (NO) in the splanchnic circulation contributes to elevated plasma levels of NO observed in decompensated cirrhosis. We evaluated in rat mesenteric arteries whether the differences in basal release of NO, revealed by asymmetric dimethylarginine (ADMA)- and N(G) -nitro-L-arginine methyl ester (L-NAME)-induced contractions, were associated with changes in messenger RNA (mRNA) expression of endothelial NO synthase (eNOS) and dimethylarginine dimethylaminohydrolases (DDAHs).

Methods: Rat small mesenteric arteries from 14 Sham-control, from 14 with partial portal vein ligation (PPVL), and from 14 with bile duct excision (BDE)-induced cirrhosis were precontracted under isometric conditions with norepinephrine, and additional contractions were induced with ADMA and L-NAME.

View Article and Find Full Text PDF

Objective: Previous studies have shown that asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA) and nitric oxide (NO) play a prominent role in liver dysfunction. The objective of this study was to determine whether plasma levels of ADMA, SDMA and NO are altered in patients with chronic hepatitis C.

Material And Methods: Plasma levels of ADMA, SDMA and NO (nitrite plus nitrate) were measured in 22 patients with chronic hepatitis C and 24 patients with sustained virologic response after treatment with peginterferon plus ribavirin.

View Article and Find Full Text PDF

Objective: The present experiments were designed to evaluate differences in the effects of cyclooxygenase (COX)-1 and COX-2 inhibition on contractile responses of human gastroepiploic artery and saphenous vein elicited by vasopressin.

Design: Laboratory investigation.

Setting: University laboratory.

View Article and Find Full Text PDF

Background: The aim of the present study was to evaluate the intervention of COX-1- and COX-2-derived prostaglandins in the responses of human gastroepiploic artery to sympathetic stimulation and norepinephrine.

Methods: Rings of human gastroepiploic artery were obtained from 45 patients (26 men and 19 women) undergoing gastrectomy. The rings were suspended in organ baths for isometric recording of tension.

View Article and Find Full Text PDF

Background: We studied the participation of K(+) channels on the adrenergic responses in human saphenous veins as well as the intervention of dihydropyridine-sensitive Ca(2+) channels on modulation of adrenergic responses by K(+) channels blockade.

Methods: Saphenous vein rings were obtained from 40 patients undergoing coronary artery bypass surgery. The vein rings were suspended in organ bath chambers for isometric recording of tension.

View Article and Find Full Text PDF