Abstract
The mammalian antidiuretic hormone, 8-arginine-vasopressin, was found to increase net mucosal-to-serosal urea flux across the isolated toad urinary bladder 13-fold. This urea flux was accompanied by a 24-fold increase in solute-linked water movement across the membrane. Net urea flux and urea-linked volume flux were inhibited by 50% or more when thiourea was added to the mucosal medium at concentrations equal to those of urea. In contrast, thiourea did not inhibit osmotic water flux across the bladder in the presence of vasopressin. These observations are consistant with the view that thiourea and urea compete for a common site on a membrane carrier molecule.
When bladders were exposed to vasopressin on the serosa and subsequently fixed with 1% glutaraldehyde on the mucosa, they were found to retain 74% of their prefixation permeability to urea. Net urea flux across these fixed bladders (in the absence of vasopressin) was markedly inhibited by thiourea, whereas osmotic water flux was not inhibited. These studies suggest that vasopressin induces the formation of “urea-channels” in the membrane that can be preserved by glutaraldehyde and blocked by thiourea.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- BENTLEY P. J. The effects of neurohypophysial extracts on the water transfer across the wall of the isolated urinary bladder of the toad Bufo marinus. J Endocrinol. 1958 Sep;17(3):201–209. doi: 10.1677/joe.0.0170201. [DOI] [PubMed] [Google Scholar]
- Eggena P. Glutaraldehyde-fixation method for determining the permeability to water of the toad urinary bladder. Endocrinology. 1972 Jul;91(1):240–246. doi: 10.1210/endo-91-1-240. [DOI] [PubMed] [Google Scholar]
- Eggena P. Osmotic regulation of toad bladder responsiveness to neurohypophyseal hormones. J Gen Physiol. 1972 Dec;60(6):665–678. doi: 10.1085/jgp.60.6.665. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eggena P., Schwartz I. L., Walter R. A sensitive hydroosmotic toad bladder assay. Affinity and intrinsic activity of neurohypophyseal peptides. J Gen Physiol. 1968 Sep;52(3):465–481. doi: 10.1085/jgp.52.3.465. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Eggena P. Temperature dependence of vasopressin action on the toad bladder. J Gen Physiol. 1972 May;59(5):519–533. doi: 10.1085/jgp.59.5.519. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grantham J. J., Burg M. B. Effect of vasopressin and cyclic AMP on permeability of isolated collecting tubules. Am J Physiol. 1966 Jul;211(1):255–259. doi: 10.1152/ajplegacy.1966.211.1.255. [DOI] [PubMed] [Google Scholar]
- LEAF A., HAYS R. M. Permeability of the isolated toad bladder to solutes and its modification by vasopressin. J Gen Physiol. 1962 May;45:921–932. doi: 10.1085/jgp.45.5.921. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MAFFLY R. H., HAYS R. M., LAMDIN E., LEAF A. The effect of neurohypophyseal hormones on the permeability of the toad bladder to urea. J Clin Invest. 1960 Apr;39:630–641. doi: 10.1172/JCI104078. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meienhofer J., Trzeciak A., Havran R. T., Walter R. A solid-phase synthesis of (8-arginine)-vasopressin through a crystalline protected nonapeptide intermediate and biological properties of the hormone. J Am Chem Soc. 1970 Dec 2;92(24):7199–7202. doi: 10.1021/ja00727a031. [DOI] [PubMed] [Google Scholar]
- Morgan T., Berliner R. W. Permeability of the loop of Henle, vasa recta, and collecting duct to water, urea, and sodium. Am J Physiol. 1968 Jul;215(1):108–115. doi: 10.1152/ajplegacy.1968.215.1.108. [DOI] [PubMed] [Google Scholar]
- SABATINI D. D., BENSCH K., BARRNETT R. J. Cytochemistry and electron microscopy. The preservation of cellular ultrastructure and enzymatic activity by aldehyde fixation. J Cell Biol. 1963 Apr;17:19–58. doi: 10.1083/jcb.17.1.19. [DOI] [PMC free article] [PubMed] [Google Scholar]