Tetracycline-induced inhibition of Na+ transport in the toad urinary bladder.
The effects of three tetracyclines, demethylchlortetracycline (DMC), minocycline (MNC), and oxytetracycline (OTC), on Na+ transport (measured as short-circuit current) were examined in toad urinary bladders mounted in modified Ussing chambers. During a 1-h incubation period serosal DMC (but not MNC or OTC) inhibited basal Na+ transport, whereas MNC (but not DMC or OTC) inhibited ADH-stimulated Na+ transport. MNC also inhibited cyclic AMP-stimulated Na+ transport. During longer incubation periods all three drugs inhibited basal Na+ transport. The DMC-induced inhibition of basal Na+ transport and the MNC-induced inhibition of ADH-stimulated Na+ transport were paralleled by an inhibition of the active conductance of the bladders. Thus, although all three drugs inhibit basal Na+ transport, only MNC inhibits ADH-stimulated Na+ transport. This effect does not correlate with the known effects of the tetracyclines on ADH-stimulated water flow or with drug-protein binding, and may be related to the greater lipid solubility of MNC.
Published In/Presented At
Guzzo, J., Cox, M., Kelley, A. B., & Singer, I. (1978). Tetracycline-induced inhibition of Na+ transport in the toad urinary bladder. The American journal of physiology, 235(4), F359–F366. https://doi.org/10.1152/ajprenal.1978.235.4.F359
Medicine and Health Sciences
Department of Medicine