Summary
The role of Ca2+ in the stimulation by antidiuretic hormone (ADH) of active sodium transport across the isolated epithelium of frog skin was investigated. This has been done by bathing the blood side with Ca2+-free solution containing 0.1mm EGTA. This Ca2+ depletion halved the resistance but had no significant effect on the short-circuit current (SCC). The sensitivity of both cAMP- and SCC-stimulation to ADH was increased 40-fold by Ca2+ depletion. Sensitivity to stimulation by theophylline was only changed a little, while stimulation by exogenous cAMP was completely unaltered. The increase in sensitivity to ADH was dependent on the duration of preincubation in Ca2+-free solution, which indicates that a slowly exchanging Ca2+ pool is involved in the determination of sensitivity to ADH. We suggest this pool is of cellular origin and the increased sensitivity is due to the decrease of a Ca2+ inhibition of the ADH-stimulated adenylate cyclase. But a direct effect of Ca2+ on binding of ADH to the receptor cannot be excluded. Our results are not compatible with the hypothesis that entry of extracellular Ca2+ is an obligatory step in the natriferic action of ADH, although it may be so in the hydroosmotic action of ADH. We also found the maximal response to ADH to be higher after Ca2+ depletion. This is in agreement with the hypothesis of intracellular Ca2+ as a modulator of the sodium permeability of the outward-facing membrane.
Similar content being viewed by others
References
Argy, W. P., Handler, J. S., Orloff, J. 1967. Ca2+ and Mg2+ effects on toad bladder response to cyclic AMP, theophyline, and ADH analogues.Am. J. Physiol. 213:803–808
Balaban, R. S., Mandel, L. J. 1979. Comparison of the effects of increased intracellular calcium and antidiuretic hormone on active transport in frog skin.Biochim. Biophys. Acta 555:1–12
Bentley, P. J. 1974. Effects of verapamil on the short-circuit current of an epithelial membrane: The toad urinary bladder.J. Pharmacol. Exp. Ther. 189:563–569
Berridge, M. J. 1975. The interaction of cyclic nucleotides and calcium in the control of cellular activity.In: Advances in Cyclic Nucleotide Research. P. Greengard and G. A. Robinson, editors. Vol. 6, pp. 1–98. Raven Press, New York
Bockaert, J., Roy, C., Jard, S. 1972. Oxytocin-sensitive adenylate cyclase in frog bladder epithelial cells. Role of calcium, nucleotides, and other factors in hormonal stimulation.J. Biol. Chem. 247:7073–7081
Borle, A. B. 1970. Kinetic analysis of calcium movements in cell cultures. III. Effects of calcium and parathyroid hormone in kidney cells.J. Gen. Physiol. 55:163–186
Campbell, B. J., Woodward, G., Borberg, V. 1972. Calciummediated interactions between the antidiuretic hormone and renal plasma membranes.J. Biol. Chem. 247:6167–6179
Curran, P. F., Zadunaisky, J., Gill, J. R. 1961. The effect of ethylenediaminetetraacetate on ion permeability of the isolated frog skin.Biochim. Biophys. Acta 52:392–395
De Sousa, R. C., Gross, A. 1973. Interactions of diphenylhydantoin with norepinephrine, theophylline and cyclic AMP in frog skin.Experientia 29:748–749
Geisler, A., Klysner, R., Thams, P., Christensen, S. 1977. A simple and inexpensive protein binding assay for cyclic AMP in biological materials.Acta Pharmacol. Toxicol. 40:356–368
Grinstein, S., Erlij, D. 1978. Intracellular calcium and the regulation of sodium transport in the frog skin.Proc. R. Soc. London 202:353–360
Handler, J. S., Orloff, J. 1973. The mechanism of action of antidiuretic hormone.In: Handbook of Physiology, Section 8. J. Orloff and R. W. Berliner, editors. pp. 791–814. American Physiological Society, Washington, D.C.
Humes, H. D., Simmons, C. F., Brenner, B. M. 1980. Effect of verapamil on the hydroosmotic response to antidiuretic hormone in toad urinary bladder.Am. J. Physiol. 239:F250-F257
Jard, S. 1974. Adrenergic receptors in epithelia.In: Drugs and Transport Processes. B. A. Callingham, editor. pp. 111–127. Macmillan Press, New York
Johnsen, A. H., Nielsen, R. 1978. Effects of the antidiuretic hormone, arginine vasotocin, theophylline, filipin and A23187 on cyclic AMP in isolated frog skin epithelium (Rana temporaria).Acta Physiol. Scand. 102:281–289
Johnsen, A. H., Nielsen, R. 1980. Sodium nitroprusside induced cGMP accumulation in isolated frog skin epithelium. Effect of cAMP, hydroosmotic and natriferic response to antidiuretic hormone.Acta Physiol. Scand. 108:373–379
Johnsen, A. H., Nielsen, R. 1981. Is cAMP a second messenger of antidiuretic hormone?Acta Physiol. Scand. 112:5A
Levine, S. D., Kachadorian, W. A., Levin, D. N., Schlondorff, D. 1981. Effects of trifluoperazine on function and structure of toad urinary bladder. Role of calmodulin in vasopressin-stimulation of water permeability.J. Clin. Invest. 67:662–672
Nielsen, R. 1978. Effect of the polyene antibiotic filipin and the calcium ionophore A23187 on sodium transport in isolated frog skin(Rana temporaria) J. Membrane Biol. Special Issue:331–345
Omachi, R. S., Robbie, D. E., Handler, J. S., Orloff, J. 1974. Effects of ADH and other agents on cyclic AMP accumulation in toad bladder epithelium.Am. J. Physiol. 226:1152–1157
Petersen, M. J., Edelman, I. S. 1964. Calcium inhibition of the action of vasopressin on the urinary bladder of the toad.J. Clin. Invest. 43:583–594
Pietras, R. J., Naujokaitis, P. J., Szego, C. M. 1976. Differential effects of vasopressin on the water, calcium and lysosomal enzyme contents of mitochondria-rich and lysome-rich (granular) epithelial cell isolated from bullfrog urinary bladder.Mol. Cell. Endocrinol. 4:89–106
Roy, C., Bockaert, J., Rajerison, R., Jard, S. 1973. Oxytocin receptor in frog bladder epithelial cells. Relationship of3H-oxytocin binding to adenylate cyclase activation.FEBS Lett. 30:329–334
Taylor, A. 1975. Effect of quinidine on the action of vasopressin.Fed. Proc. 34:285
Taylor, A., Windhager, E. E. 1979. Possible role of cytosolic calcium and Na-Ca exchange in regulation of transepithelial sodium transport.Am. J. Physiol. 236:F505-F512
Ussing, H. H., Zerahn, K. 1951. Active transport of sodium as the source of electric current in the short-circuited isolated frog skin.Acta Physiol. Scand. 23:110–127
Zadunaisky, J. A., Lande, M. A. 1972. Calcium content and exchange in amphibian skin and its isolated epithelium.Am. J. Physiol. 222:1309–1315
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Johnsen, A.H., Nielsen, R. Enhanced sensitivity to stimulation of sodium transport and cyclic AMP by antidiuretic hormone after Ca2+ depletion of isolated frog skin epithelium. J. Membrain Biol. 69, 137–143 (1982). https://doi.org/10.1007/BF01872273
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF01872273