Endothelin-1 kinetics in plasma, urine, and blister fluid in burn patients

Therapeutic role of taurine as antioxidant in reducing hypertension risks in rats

AIM

The current investigation focused on the therapeutic role of the administration of taurine on hypertensive rats to reduce or cure the hazard effects of hypertension problems.

METHODOLOGY

This research included 2 experiments; 1st was done to survey the variations that might occur in blood pressure (BP) of male rats because of the fed 8% NaCl diet for 4 weeks. 2nd experiment, it contains normal control rats', hypertensive rats were served as hypertension recovery group and hypertensive rats were took orally by the help of gastric tube 50 mg taurine/100 g b.wt/day for four weeks and served as taurine group.

RESULTS

1st experimental, clarified a significant elevation in BP, body weight, serum cholesterol, triglycerides, LDL, activities of serum cardiac enzymes, endothelin-1, ADMA, MDA and TNF-α in hypertensive rats' group. On contrary, there is a significant reduction in serum level of TNO and antioxidant enzymes level in relation to the control group. A numerical variation but not statistically significant was happened in HDL in hypertensive rats' group as compared to their matching results in control rats' group. 2nd experimental taurine significantly reduced the BP as compared with hypertensive control. Furthermore, a significant improvement occurred in the mean value of most investigation parameters in hypertensive animal group which treated with taurine.

CONCLUSION

The previous data could be concluded that, there is an obvious amelioration effects of taurine on hypertensive rats by reducing the hazard effects of hypertension problems. The primary mechanisms were discussed according to existing published investigations.

Increased endothelin-1 and diminished nitric oxide levels in blister fluids of patients with intermediate cold type complex regional pain syndrome type 1

Background

In complex regional pain syndrome type 1 (CRPS1) pro-inflammatory mediators and vascular changes play an important role in the sustained development and outcome of the disease. The aim of this study was to determine the involvement of vasoactive substances endothelin-1 (ET-1) and nitric oxide (NO) during early chronic CRPS1.

Methods

Included were 29 patients with CRPS 1 who were diagnosed during the acute stage of their disease and observed during follow-up visits. Disease activity and impairment were determined and artificial suction blisters were made on the CRPS1 and the contralateral extremities for measurements of IL-6, TNF-α, ET-1 and nitrate/nitrite (NOx).

Results

The levels of IL-6, TNF-α and ET-1 in blister fluid in the CRPS1 extremity versus the contralateral extremity were significantly increased and correlated with each other, whereas NOx levels were decreased.

Conclusion

The NOx/ET-1 ratio appears to be disturbed in the intermediate stage of CRPS, resulting in vasoconstriction and consequently in a diminished tissue blood distribution.

Plasma endothelin-1 level as a marker reflecting the severity of portal hypertension in biliary atresia

BACKGROUND/PURPOSE

The aim of this study was to examine if the plasma endothelin-1 (ET-1), a potent vasoconstrictor, level may reflect the severity of portal hypertension associated with liver cirrhosis in biliary atresia (BA).

METHODS

Forty-eight postoperative BA patients aged 6 months to 20 years were studied. Plasma ET-1 was measured by a sandwich method of enzyme immunoassay. ET-1 was compared with Child's score and laboratory data. ET-1 levels were compared among groups of patients with various degrees of histologic fibrosis and portal hypertension.

RESULTS

Plasma ET-1 was 5.3 +/- 3.5 pg/mL in BA, higher than in controls (3.1 +/- 0.8, n = 27; P <.05). ET-1 correlated with Child's score, serum total bilirubin, direct bilirubin, aspartate aminotransferase, albumin, prothrombin time, hepaplastin test, fibrinogen, cholinesterase, total cholesterol, Fischer's molar ratio, prealubumin, and hyaluronic acid, respectively (P <.05). ET-1 also correlated with the severity of histologic fibrosis, gastroesophageal varices, the presence of splenomegaly, ascites, venous dilatation on the abdominal wall, or pulmonary vascular abnormalities. In 4 patients undergoing liver transplantation (LTx), ET-1 after LTx was lower than that before LTx (P <.05).

CONCLUSION

Plasma ET-1 level may be a useful index reflecting the severity of cirrhosis and portal hypertension in BA.

Effects of nitric oxide synthase inhibitors on vascular hyperpermeability with thermal injury in mice

The role of nitric oxide and related synthase in thermal injury was investigated by using models of experimental burn to evaluate severity from the aspect of vascular permeability. Thermal injuries were produced in the murine right ear by pinching with a pair of preheated tweezers. Immediately thereafter, Evans blue dye was intravenously administered, and the mice injured with burns were sacrificed at various times. The burned ears were collected and hydrolyzed, and the level of extracted dye was measured as an indicator of inflammation. Vascular hyperpermeability was suppressed by the administration of nitric oxide synthase inhibitors. LNAME not only suppressed vascular hyperpermeability in thermal injuries in a dose-dependent manner but was also effective with either prophylactic or therapeutic administration. Although aminoguanidine also suppressed the inflammatory response, it had no effect on the early inflammatory phase. Nitric oxide synthase is well known to have two types of isozymes. Aminoguanidine, an inhibitor specific to inducible nitric oxide synthase, suppressed the late phase 6 h after injury, suggesting that inducible nitric oxide synthase is involved in inflammatory responses of thermal injuries. These results also demonstrated that inducible nitric oxide synthase-like protein stained the burned region immunohistochemically. Therefore, both types of enzymes mediating nitric oxide affect inflammatory responses, i.e., vascular hyperpermeability, and their regulation may lead to the development of new therapy for thermal injuries.

Urinary endothelin in adolescents and young adults with insulin-dependent diabetes mellitus: relation to urinary albumin, blood pressure, and other factors

Endothelin (ET) is a potent vasoconstrictive peptide that may play a role in vascular pathology in general and diabetic nephropathy in particular. The aim of this study was to investigate (1) alterations of urinary ET1 (UET1) in adolescents and young adults with insulin-dependent diabetes mellitus (IDDM) and (2) the relation of UET1 to other indices of diabetic nephropathy and to risk factors of diabetic angiopathy in general. In 130 IDDM subjects aged 15.2+/-4.9 years with a diabetes duration of 7.3+/-5.1 years, UET1 by radioimmunoassay, urinary albumin by nephelometry, plasma renin by immunoradiometric assay, hemoglobin A1c (HbA1c) by high-performance liquid chromatography, and routine biochemistry analyses were determined. Forty-eight controls, healthy siblings of the diabetics of comparable age, were similarly studied. Total 24-hour UET1 excretion was higher in diabetics than in controls (10,866+/-7,270 and 6,598+/-3,294 pg/24 h, respectively, P=.000). This difference was also noted if male and female diabetics were separately compared with controls. In diabetics with normoalbuminuria (<20 microg/min), total 24-hour UET1 excretion was also higher than in controls (P=.002). In diabetics but not in controls, 24-hour UET1 values were higher in males than in females (P=.018). In IDDM subjects, UET1 showed a linear relationship with age (P=.002), urinary albumin (P=.000), serum creatinine (P=.001), systolic blood pressure (P=.038), triglycerides (P=.003), and HbA1c (P=.041). Multiple regression analysis demonstrated that the variables interacting independently with UET1 were urinary albumin (P=.003) and serum creatinine (P=.038). UET1 is elevated early (in adolescence) in IDDM subjects, and it is positively correlated with the degree of albuminuria. These data suggest that the amount of UET1 possibly reflects the severity of diabetic renovascular damage. It may thus be speculated that UET1 could be used as another index of diabetic nephropathy or its progress.