Species differences in the response of sugar and amino acid transport.

Transport of xylose, glycine and leucine at six different concentrations (1.25, 2.5, 5.0, 10.0, 25.0 and 50.0 mM) has been studied in Ophiocephalus punctatus and Heteropneustes fossilis. With the increase in the concentration of the compounds in the filling solution, a corresponding increase is brought about in the transport rate. On a further increase in the concentration of the compounds transport rate is reduced. The transport of these nutrients has also been determined at 15, 30, 60, 90, 120, 180 and 240 min intervals. Absorption is significant even at the 15 min stage. At low concentrations of the sugars and leucine, the process was more active in comparison to higher concentrations. Variations in the transport of nutrients were noted in the two fishes.