Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The renal effects of endothelin-1 were investigated in 16 anesthetized and mechanically ventilated newborn rabbits. Renal blood flow and glomerular filtration rate were determined by the clearance of para-aminohippuric acid and inulin, respectively. Each animal acted as its own control. In eight newborn rabbits, a bolus injection of 5 nmol.kg-1 of endothelin-1 caused an initial fall in mean arterial blood pressure followed by a gradual, significant increase in mean arterial blood pressure that lasted for 45 min. The dramatic increase in renal vascular resistance (+28 +/- 4%) induced by endothelin led to a fall in glomerular filtration rate (-12 +/- 4%) and renal blood flow (-16 +/- 3%). In spite of the reduction of glomerular filtration rate and renal blood flow, urine flow and sodium excretion rates increased significantly (+20 +/- 5% and +49 +/- 9%, respectively). In eight additional newborn rabbits, a bolus injection of 1 nmol.kg-1 of endothelin--a dose that usually induces marked renal and systemic vasoconstriction in adult models--did not affect systemic or renal hemodynamics. In conclusion, endothelin induces renal and systemic vasoconstriction and affects water and sodium homeostasis during the neonatal period. These effects occur under higher doses than those used in adult animals. This age difference in systemic and renal responsiveness is probably mediated by receptor immaturity and/or interference of high levels of counteracting hormones present during the neonatal period.
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PMID:Effects of endothelin on renal function in newborn rabbits. 823 10

In addition to the immaturity of air sacs and surfactant deficiency, preterm infants with respiratory distress syndrome (RDS) have abnormalities in the pulmonary vascular bed. We aimed to study two known modulators of pulmonary vessels: endothelin-1 (ET-1) and L-arginine. We hypothesized that plasma concentrations of ET-1 and L-arginine could correlate with the severity of RDS. We prospectively studied 71 preterm infants (gestational age = 29 to 35 weeks) with and without RDS. We measured plasma ET-1 by enzyme-linked immunosorbent assay and L-arginine by spectrophotometry. Infants who continued to require oxygen support or died by day of life 28 were considered to have bronchopulmonary dysplasia (BPD). ET-1 concentrations were significantly higher in RDS infants ( p = 0.039) than controls. Among infants with RDS, it was significantly higher in those who later developed BPD ( p = 0.026). L-arginine was significantly lower in RDS infants ( p = 0.001), but did not differ between BPD and non-BPD infants ( p = 0.19). There was no correlation between L-arginine and ET-1 ( r = 0.1, p = 0.41). The acute phase of RDS is associated with increased plasma concentrations of ET-1 and decreased L-arginine. Infants who later developed BPD had higher plasma ET-1 at birth. Concentrations of ET-1 and L-arginine did not correlate.
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PMID:Endothelin-1 and L-arginine in preterm infants with respiratory distress. 2070 Aug 64