{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T21:11:32Z","timestamp":1778274692305,"version":"3.51.4"},"reference-count":0,"publisher":"American Physiological Society","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["American Journal of Physiology-Cell Physiology"],"published-print":{"date-parts":[[1992,2,1]]},"abstract":"<jats:p> Many cells respond to shrinkage by stimulating specific ion transport processes (e.g., Na-H exchange). However, it is not known how the cell senses this volume change, nor how this signal is transduced to an ion transporter. We have studied the activation of Na-H exchange in internally dialyzed barnacle muscle fibers, measuring intracellular pH (pHi) with glass microelectrodes. When cells are dialyzed to a pHi of approximately 7.2, Na-H exchange is active only in shrunken cells. We found that the shrinkage-induced stimulation of Na-H exchange, elicited by increasing medium osmolality from 975 to 1,600 mosmol\/kgH2O, is inhibited approximately 72% by including in the dialysis fluid 1 mM guanosine 5'-O-(2-thiodiphosphate). The latter is an antagonist of G protein activation. Even in unshrunken cells, Na-H exchange is activated by dialyzing the cell with 1 mM guanosine 5'-O-(3-thiotriphosphate), which causes the prolonged activation of G proteins. Activation of Na-H exchange is also elicited in unshrunken cells by injecting cholera toxin, which activates certain G proteins. Neither exposing cells to 100 nM phorbol 12-myristate 13-acetate nor dialyzing them with a solution containing 20 microM adenosine 3',5'-cyclic monophosphate (cAMP) (or 50 microM dibutyryl cAMP) plus 0.5 mM 3-isobutyl-1-methylxanthine substantially stimulates the exchanger. Thus our data suggest that a G protein plays a key role in the transduction of the shrinkage signal to the Na-H exchanger via a pathway that involves neither protein kinase C nor cAMP. <\/jats:p>","DOI":"10.1152\/ajpcell.1992.262.2.c533","type":"journal-article","created":{"date-parts":[[2017,12,24]],"date-time":"2017-12-24T13:06:43Z","timestamp":1514120803000},"page":"C533-C536","source":"Crossref","is-referenced-by-count":42,"title":["Role of G proteins in stimulation of Na-H exchange by cell shrinkage"],"prefix":"10.1152","volume":"262","author":[{"given":"B. A.","family":"Davis","sequence":"first","affiliation":[{"name":"Department of Cellular and Molecular Physiology, Yale UniversitySchool of Medicine, New Haven, Connecticut 06510."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"E. M.","family":"Hogan","sequence":"additional","affiliation":[{"name":"Department of Cellular and Molecular Physiology, Yale UniversitySchool of Medicine, New Haven, Connecticut 06510."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"W. F.","family":"Boron","sequence":"additional","affiliation":[{"name":"Department of Cellular and Molecular Physiology, Yale UniversitySchool of Medicine, New Haven, Connecticut 06510."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"24","container-title":["American Journal of Physiology-Cell Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.physiology.org\/doi\/pdf\/10.1152\/ajpcell.1992.262.2.C533","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,6,17]],"date-time":"2024-06-17T19:44:44Z","timestamp":1718653484000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.physiology.org\/doi\/10.1152\/ajpcell.1992.262.2.C533"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1992,2,1]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1992,2,1]]}},"alternative-id":["10.1152\/ajpcell.1992.262.2.C533"],"URL":"https:\/\/doi.org\/10.1152\/ajpcell.1992.262.2.c533","relation":{},"ISSN":["0363-6143","1522-1563"],"issn-type":[{"value":"0363-6143","type":"print"},{"value":"1522-1563","type":"electronic"}],"subject":[],"published":{"date-parts":[[1992,2,1]]}}}