Renal slice uptake of organic acid and sugar in pouch young of the marsupial Trichosurus vulpecula

Abstract

Kidney tissue was collected from 14 pouch young of the brushtailed possum Trichosurus vulpecula. The young were aged from 5 to 143 days postpartum. Histological observation of a 6-day mesonephric kidney revealed a well-defined microvillus brushborder lining the lumen of the proximal tubule. Renal slices from all the pouch young tested, including mesonephric and metanephric tissue, accumulated p-aminohippurate and α- methyl-d-glucoside at rates comparable to adult renal cortical slices. Tissue to medium concentration ratios after 1 h of uptake averaged 3.8 for p-aminohippurate and 1.9 for α-methyl-d-glucoside in the young. It was concluded that proximal nephron morphology and the transport systems involved in organic acid secretion and sugar reabsorption by the kidney were well-developed at all stages of pouch life.