{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:39:25Z","timestamp":1790642365327,"version":"4.1.0"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"21","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1994,10,11]]},"abstract":"<jats:p>We have investigated the changes of cytosolic [Ca2+] and the secretory activity in single glomus cells dispersed from rabbit carotid bodies during exposure to solutions with variable O2 tension (Po2). In normoxic conditions (Po2 = 145 mmHg; 1 mmHg = 133 Pa), intracellular [Ca2+] was 58 +\/- 29 nM, and switching to low Po2 (between 10 and 60 mmHg) led to a reversible increase of [Ca2+] up to 800 nM. The response to hypoxia completely disappeared after removal of external Ca2+ or with the addition of 0.2 mM Cd2+ to the external solution. These same solutions also abolished both the Ca2+ current of the cells and the increase of internal [Ca2+] elicited by high external K+. Elevations of cytosolic [Ca2+] in response to hypoxia or to direct membrane depolarization elicited the release of dopamine, which was detected by amperometric techniques. Dopamine secretion occurred in episodes of spike-like activity that appear to represent the release from single secretory vesicles. From the mean charge of well-resolved secretory events, we estimated the average number of dopamine molecules per vesicle to be approximately 140,000, a value about 15 times smaller than a previous estimate in chromaffin granules of adrenomedullary cells. These results directly demonstrate in a single-cell preparation the secretory response of glomus cells to hypoxia. The data indicate that the enhancement of cellular excitability upon exposure to low Po2 results in Ca2+ entry through voltage-gated channels, which leads to an increase in intracellular [Ca2+] and exocytotic transmitter release.<\/jats:p>","DOI":"10.1073\/pnas.91.21.10208","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T08:57:05Z","timestamp":1149065825000},"page":"10208-10211","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":179,"title":["Hypoxia induces voltage-dependent Ca2+ entry and quantal dopamine secretion in carotid body glomus cells."],"prefix":"10.1073","volume":"91","author":[{"given":"J","family":"Ure\u00f1a","sequence":"first","affiliation":[{"name":"Departamento de Fisiolog\u00eda M\u00e9dica y Biof\u00edsica, Universidad de Sevilla, Facultad de Medicina, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R","family":"Fern\u00e1ndez-Chac\u00f3n","sequence":"additional","affiliation":[{"name":"Departamento de Fisiolog\u00eda M\u00e9dica y Biof\u00edsica, Universidad de Sevilla, Facultad de Medicina, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"A R","family":"Benot","sequence":"additional","affiliation":[{"name":"Departamento de Fisiolog\u00eda M\u00e9dica y Biof\u00edsica, Universidad de Sevilla, Facultad de Medicina, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G A","family":"Alvarez de Toledo","sequence":"additional","affiliation":[{"name":"Departamento de Fisiolog\u00eda M\u00e9dica y Biof\u00edsica, Universidad de Sevilla, Facultad de Medicina, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"L\u00f3pez-Barneo","sequence":"additional","affiliation":[{"name":"Departamento de Fisiolog\u00eda M\u00e9dica y Biof\u00edsica, Universidad de Sevilla, Facultad de Medicina, Spain."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1994,10,11]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.91.21.10208","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T13:53:51Z","timestamp":1649858031000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.91.21.10208"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1994,10,11]]},"references-count":0,"journal-issue":{"issue":"21","published-print":{"date-parts":[[1994,10,11]]}},"alternative-id":["10.1073\/pnas.91.21.10208"],"URL":"https:\/\/doi.org\/10.1073\/pnas.91.21.10208","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1994,10,11]]},"assertion":[{"value":"1994-10-11","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}