Gill ammonia transport

Abstract

Abstract Ammonia theoretically can traverse the gill epithelium of aquatic animals in a variety of ways. Recent experiments utilizing both whole animals (fish and arthropods), and perfused heads of fishes indicate that diffusional movement of both NH 3 and NH 4 + takes place, as well as basolateral (serosal) Na + /NH 4 + exchange. Data supporting the presence of apical (mucosal) Na + /NH 4 + exchange are more equivocal, and there is no published evidence for transport via basolateral NH 4 Cl + NaCl co‐transport. The relative roles of various pathways may depend upon the species and its salinity of acclimation.