Abstract
ABSTRACT. Developmental changes in cystine transport by the canine kidney were examined both in vivo and in vitro. Renal clearance studies indicated that cystine was one of the more incompletely reabsorbed amino acids at birth, but its reabsorption approaches adult levels by 21 days. Concomitantly, cystine uptake by isolated renal cortical tubule fragments from immature dogs was slower than that by renal tubules from adult dogs. Both age groups rapidly metabolized the transported cystine. This metabolism was principally to cysteine, but also small amounts of reduced glutathione were formed from the transported cystine. Concentration dependence studies indicated two transport systems for cystine uptake in both the immature and the adult dog. Both transport systems in the 1-wk-old dog had a somewhat greater affinity for cystine than the corresponding system in the adult, but this was offset by the markedly lower maximal transport rates for these, systems in the 1-wk-old dog. The high affinity system was inhibited by lysine in tubules from both age groups. In the dog, the rise in the tubular reabsorption of cystine with maturation could, in part, be explained by an increase in the number of transport sites for cystine.
Similar content being viewed by others
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Foreman, J., Medow, M., Bovee, K. et al. Developmental Aspects of Cystine Transport in the Dog. Pediatr Res 20, 593–597 (1986). https://doi.org/10.1203/00006450-198607000-00003
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1203/00006450-198607000-00003
This article is cited by
-
Renal amino acid transport: cellular and molecular events from clearance studies to frog eggs
Pediatric Nephrology (1993)
-
The role of protein phosphorylation in renal amino acid transport
Pediatric Nephrology (1993)
-
The renal transport of taurine and the regulation of renal sodium-chloride-dependent transporter activity
Pediatric Nephrology (1990)
-
Cystine uptake by cultured cells originating from dog proximal tubule segments
In Vitro Cellular & Developmental Biology (1990)
-
Sodium-coupled amino acid transport in renal tubule
Kidney International (1989)