Fig. 2.
Ex vivo kinetic analysis of basolateral transport of [3H]uridine by rodent seminiferous tubules. Composite graphs demonstrating basolateral [3H]uridine transport by rat (A) or mouse (B) intact seminiferous tubules in the presence of increasing concentrations of unlabeled uridine. The mean concentrations of [3H]uridine in the baths were 0.45 and 0.37 µM for rats and mice, respectively. The Kt values were calculated to be 314 and 90 μM for rat and mouse seminiferous tubules, respectively. Each point represents an average (± S.E.) of at least five different experiments, each with a different animal. Insets demonstrate Eadie-Hofstee transformation of the data. At least three separate tubules for each unlabeled uridine concentration were analyzed in each experiment.