endothelin-1 and Hydronephrosis

Congenital hydronephrosis is induced by congenital obstruction of uretero pelvic junction, bladder vesicoureteral reflux, posterior urethral valve, stricture of ureter end and ureterocyst, which is extremely apt to cause end-stage renal failure in children. It becomes significant to explore the expression profile and clinical significance of aquaporin-1 (AQP-1) and ET-1 (endothelin-1) in the urine of children with congenital hydronephrosis.. 80 cases of children with congenital hydronephrosis were selected to be the observation group and another 40 cases of children with other diseases were served as control group. Pre-operative morning urine, intra-operative renal pelvis urine and morning urine at the 7th day after the operation of all the children were collected for the detection of the level of ET-1, Cr level and AQP1 in the urine. Urine various indexes of different diseases stages in children of both groups were compared.. There was no significant difference between children with mild and children in control group (p > 0.05). In the observation group, the AQP-1 level during the operation was significantly lower than that before operation, but it was significantly higher in post-operation than that during the operation, which was still lower than that in control group (p < 0.05). Urine ET-1 level in observation group and its positive rate were significantly higher than that in control group (p < 0.05). Serum stress indexes in each stage of the observation group were significantly higher than that in control group (p < 0.05).. The expression levels of urine AQP-1 and ET-1 of children with congenital hydronephrosis were obviously increased. The AQP-1 level during the operation was lower than that before operation. This post-operation level was significantly higher than before the operation. The expression of AQP-1 and ET-1 could be used as important indexes for clinical diagnosis.

Topics: Aquaporin 1; Case-Control Studies; Child, Preschool; Constriction, Pathologic; Endothelin-1; Female; Humans; Hydronephrosis; Infant; Kidney Pelvis; Male; Postoperative Period; Ureter; Vesico-Ureteral Reflux

Antenatal hydronephrosis (AH) is found in 0.5%-1% of neonates. The aim of the study was to assess the urinary concentrations of 3 biomarkers, endothelin-1 (ET-1), monocyte chemotactic peptide-1 (MCP-1), and N-acetyl-glucosaminidase (NAG) in severely hydronephrotic neonates.. Neonates with a history of prenatal hydronephrosis were enrolled in the prospective study in 2 groups. Group 1 included neonates with severe forms of obstruction requiring surgical intervention and group 2 included neonates with milder forms of obstruction without any functional impairment. Fresh voided urinary levels of ET-1, MCP-1, and NAG were measured and their ratios to urinary Cr were calculated.. Fourty-two neonates were enrolled into the 2 groups: group 1, 24 patients (21 male, 3 female); group 2, 18 neonates (16 male, 2 female). There were no statistically significant differences between urinary ET-1, NAG, MCP-1 values, and ET-1/Cr and NAG/Cr ratios in groups 1 and 2. The urinary MCP-1/Cr ratio was significantly higher in group 1 than in group 2. For comparison of groups 1 and 2, the cut-off values were measured as 0.5709 ng/mg (sensitivity, 75%; specificity, 67%; positive predictive value [PPV], 71%; negative predictive value [NPV], 71%), 0.927 ng/mg (sensitivity, 77%; specificity, 72%; PPV, 77%; NPV, 72%), and 1.1913 IU/mg (sensitivity, 62%; specificity, 67%; PPV, 68%; NPV, 60%) for ET-1/Cr, MCP-1/Cr, and NAG/Cr ratios, respectively.. The urinary MCP-1/Cr ratio is significantly elevated in neonates with severe obstruction requiring surgical intervention. Based upon these results, urinary MCP-1/Cr may be useful in identification of severe obstructive hydronephrosis in neonates.

Topics: Acetylglucosaminidase; Biomarkers; Chemokine CCL2; Endothelin-1; Female; Humans; Hydronephrosis; Infant, Newborn; Male; Predictive Value of Tests; Prospective Studies; Sensitivity and Specificity; Ultrasonography; Ureteral Obstruction

Hydronephrosis is a common finding in patients with urinary tract infection (UTI). Endothellin-1 (ET-1) is a potent vasoactive peptide that has vasoconstrictive effects. It has been shown that urinary ET-1 increases in urinary obstructions. In this study, we measured the urinary ET-1 level in patients with UTI and hydronephrosis of various causes. In this case-control study, we evaluated the urinary ET-1 level in 45 patients who had UTI and hydronephrosis, serving as a case group, and 45 patients who had UTI without hydronephrosis, serving as a control group. Urinary ET-1 was quantified using enzyme-linked immunosorbent assay and urinary creatinine (Cr) by Jaffe method. To rule out the effect of urinary flow rate, the urinary ET-1 to Cr correlation was considered for analysis of the results. The mean age of the patients in the case and control groups was 36.5 ± 27.2 and 26.2 ± 15.5 months, respectively (P >0.01). The mean urinary ET-1 was 89.6 ± 41.7 pg/dL in the case group and 29.3 ± 26 pg/dL in the control group, P <0.001. The mean urinary ET-1 was 121 ± 55.4 pg/dL in patients who had grade 4 hydronephrosis. We conclude that urinary ET-1 was significantly higher in the obstructed than in non-obstructed cases. Urinary ET-1 could be a useful marker that can be utilized in young children for diagnosis of hydronephrosis, especially obstructive cases.

Topics: Case-Control Studies; Endothelin-1; Female; Humans; Hydronephrosis; Infant; Male; Pyelonephritis

To investigate the expression of endothelin-1 (ET-1) and adrenomedullin (ADM) in the renal pelvis, stenotic ureteropelvic junction, and ureter of 20 male Wistar rats with congenital unilateral ureteropelvic junction obstruction; the normal contralateral kidneys served as controls. The molecular pathophysiology of congenital ureteropelvic junction obstruction is still unclear. The implication of altered peptidergic innervation is under discussion. Our study group has recently been able to demonstrate a significant increase in ET-1 and a significant decrease in ADM in prestenotic and stenotic tissue, but not in the remainder of the ureter, compared with controls.. Twenty animals were killed, and samples of the renal pelvis, ureteropelvic junction, upper ureter, middle part of the ureter, and lower ureter were immediately snap-frozen and stored in liquid nitrogen. Total RNA was extracted, and subsequently 1 microg of RNA was reversely transcribed. mRNA expression of ET-1 and ADM was determined semiquantitatively using on-line polymerase chain reaction. The expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was determined to relate the specific mRNA expression to the expression of a housekeeping gene.. We found a significant increase in the expression of ET-1 in the obstructed junctions related to GAPDH (P <0.001). The expression of ADM, however, revealed no statistically significant differences. No differences at all could be detected in the tissue samples from the rest of the ureter.. Alterations in the local production of peptidergic neurotransmitters, especially ET-1, may contribute to the molecular pathogenesis of ureteropelvic junction obstruction. Results previously obtained in the stenotic tissue from children were confirmed in the stenotic tissue from the rat model. We hypothesize that the alterations are disease-, but not age-specific.

Topics: Abnormalities, Multiple; Adrenomedullin; Animals; Atrophy; Computer Systems; Constriction, Pathologic; Disease Models, Animal; Endothelin-1; Gene Expression Profiling; Hydronephrosis; Kidney Pelvis; Male; Peptides; Polymerase Chain Reaction; Rats; Rats, Mutant Strains; Rats, Wistar; RNA, Messenger; Ureter; Ureteral Obstruction

Myogenic vasoconstriction of the renal afferent arteriole contributes to the autoregulation of renal blood flow, glomerular filtration rate, and glomerular capillary pressure (PGC). The reactivity of the afferent arteriole to pressure and the efficiency of PGC control are subject to physiological and pathophysiological alterations, but the determinants of the myogenic response of this vessel are largely unknown. We used the in vitro perfused hydronephrotic rat kidney to investigate the role of protein kinase C (PKC) in the control of this response. Inhibition of PKC by 1 microM chelerythrine attenuated myogenic reactivity but did not affect the afferent arteriole vasoconstrictor response to KCl (35 mM)-induced depolarization. Low concentrations of phorbol ester (10 nM phorbol 12-myristate 13-acetate) and low levels of ANG II or endothelin-1 (3 pM) potentiated myogenic vasoconstriction without affecting basal afferent arteriolar diameters. These actions were blocked by 1 microM chelerythrine, suggesting a PKC-dependent mechanism. Finally, although PKC inhibition attenuated basal myogenic responses, full reactivity to pressure was restored by 1 mM 4-aminopyridine, a pharmacological inhibitor of delayed rectifier K channels, which are known to be modulated by PKC. The ability of 4-aminopyridine to circumvent the effects of PKC inhibition militates against a direct role of PKC in myogenic signaling. We interpret these observations as indicating that basal PKC activity is an important determinant of myogenic reactivity in the renal afferent arteriole. However, PKC activation does not appear to play an obligate role in myogenic signaling in this vessel. We suggest that basal PKC activity directly modulates voltage-gated K channel activity, thereby indirectly affecting myogenic reactivity.

Topics: 4-Aminopyridine; Alkaloids; Angiotensin II; Animals; Arterioles; Benzophenanthridines; Blood Pressure; Delayed Rectifier Potassium Channels; Endothelin-1; Enzyme Inhibitors; Hydronephrosis; Kidney; Male; Muscle, Smooth, Vascular; Perfusion; Phenanthridines; Potassium Channel Blockers; Potassium Channels; Potassium Channels, Voltage-Gated; Potassium Chloride; Protein Kinase C; Rats; Rats, Sprague-Dawley; Renal Circulation; Tetradecanoylphorbol Acetate; Vasoconstriction

To assess the site of action of endothelin-1 in vessels of different sizes in the kidney in vivo and investigate the function of endothelin A (ET(A)) receptors in mediating renal and systemic vasoconstriction.. The luminal diameters of different vessels were measured and glomerular blood flow in cortical glomeruli was determined by intravital videomicroscopy in the split hydronephrotic kidney of anesthetized female Wistar rats.. The rats were infused with endothelin-1 (40 pmol/kg per min) with or without pretreatment with the selective ET(A)-receptor antagonist BQ-123 (0.5 mg/kg). Aortic clamping was used to control renal blood pressure during the endothelin-1 infusion.. Exogenous endothelin-1 induced a significant rise (30+/-3%) in mean arterial pressure and a marked, long-lasting fall in glomerular blood flow (53+/-3%) related to reduction of the inner diameter of arcuate (-30%), interlobular arteries (-33%) and afferent arterioles (-17%). Aortic clamping to normalize renal blood pressure did not attenuate the vasoconstriction and reduction in glomerular blood flow. Pretreatment with BQ-123 significantly reduced both the endothelin-1-induced rise in mean arterial pressure (12+/-1%) and the fall in glomerular blood flow (-23+/-11%). BQ-123 blunted the response to endothelin-1 in arcuate (-12%), interlobular (-11%) and afferent vessels (-5%). Acetylcholine and nitroprusside completely reversed the vasoconstriction in BQ-123-pretreated animals.. BQ-123 largely prevented the hemodynamic effects of exogenously administered endothelin-1. Our direct in-vivo techniques showed that ET(A) receptors are, at least in part, involved in endothelin-1 -mediated vasoconstriction in the rat kidney, and support the hypothesis that ET(A) receptors may help to control arterial pressure in anesthetized rats.

Topics: Animals; Blood Flow Velocity; Blood Pressure; Drug Therapy, Combination; Endothelin Receptor Antagonists; Endothelin-1; Female; Glomerular Filtration Rate; Hydronephrosis; Kidney Glomerulus; Microscopy, Video; Peptides, Cyclic; Rats; Rats, Wistar; Receptor, Endothelin A; Renal Artery; Renal Circulation; Vasoconstriction; Vasodilator Agents