The effect of highly alkaline water (pH 9.5) on the morphology and morphometry of chloride cells and pavement cells in the gills of the freshwater rainbow trout: relationship to ionic transport and ammonia excretion

Exposure of rainbow trout (Oncorhynchus mykiss) to alkaline water (pH 9.5) impairs ammonia excretion (J Amm ) and gill-mediated ion-exchange processes, as characterized by decreased Cl - (J C1 in ) and Na + influx (J Na in ) across the gill. Scanning electron microscopy suggested that the depression of J C1 in was concomitant with an early decrease in the population of the most active chloride cells (CCs), partly compensated for by an …