RGD Reference Report - The urinary concentrating defect in the Gunn strain of rat. Role of bilirubin. - Rat Genome Database

Send us a Message



Submit Data |  Help |  Video Tutorials |  News |  Publications |  Download |  REST API |  Citing RGD |  Contact   

The urinary concentrating defect in the Gunn strain of rat. Role of bilirubin.

Authors: Call, NB  Tisher, CC 
Citation: Call NB and Tisher CC, J Clin Invest 1975 Feb;55(2):319-29.
RGD ID: 1354700
Pubmed: PMID:1127102   (View Abstract at PubMed)
PMCID: PMC301750   (View Article at PubMed Central)
DOI: DOI:10.1172/JCI107935   (Journal Full-text)

The role of high serum and tissue levels of unconjegated bilirubin in the pathogenesis of the impaired urinary concentrating ability was investigated in homozygous (jj) Gunn rats with the congenital absence of hepatic glucuronyl transferase. Continuous phototherapy with blue fluorescent lights at a wave length of 460 nm or oral cholestyramine feeding or both reduced serum levels of unconjugated hilirubin to levels consistently below 3.0 mg/100 ml for several weeks in both weanling and adult jj Gunn rats. The renal concentrating defect was already present in weanling jj Gunn rats by 21 days of age. In treated weanling jj animals, maximum concentrating ability and the concentration of urea and nonurea solutes in the papilla and medulla, determined after 24 h of fluid deprivation, were normal when compared to unaffected heterozygous (Jj) littermates. Solute-free water reabsorption which is reduced in jaundiced jj Gunn rats was restored to normal in treated weanling jj rats. The tissue concentration of unconjugated bilirubin was reduced throughout the papilla and inner and outer medulla in the treated jj rats in comparison with untreated jj littermates. The defect in urinary concentrating ability was only partially reversible and sometimes irreversible in adult jj rats, probably because of permanent renal parenchymal damage occurring secondary to massive crystalline deposits in the papilla and medulla. It is concluded that unconjugated bilirubin is directly involved in the pathogenesis of the concentrating defect in jaundiced jj Gunn rats.

Phenotype Annotations    Click to see Annotation Detail View

Mammalian Phenotype

Objects Annotated

Genes (Rattus norvegicus)
Ugt1a1  (UDP glucuronosyltransferase family 1 member A1)
Ugt1a1j  (UDP glucuronosyltransferase family 1 member A1, jaundice mutant)

Strains
Gunn-Ugt1a1j/BluHsd  (Gunn rat)


Additional Information