{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T03:38:54Z","timestamp":1771645134779,"version":"3.50.1"},"reference-count":0,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[1971,11,1]],"date-time":"1971-11-01T00:00:00Z","timestamp":57801600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["The Journal of Physiology"],"published-print":{"date-parts":[[1971,11]]},"abstract":"<jats:p>1. In anaesthetized foetal lambs near term, hypocapnia induced by maternal hyperventilation abolished the rise of arterial pressure and femoral vasoconstriction caused by hypoxaemia. This is consistent with interaction of <jats:italic>P<\/jats:italic>CO<jats:sub>2<\/jats:sub> and <jats:italic>P<\/jats:italic>O<jats:sub>2<\/jats:sub> on the foetal aortic bodies.<\/jats:p><jats:p>2. In immature lambs (0\u00b76\u22120\u00b777 of term) maternal hyperventilation caused a fall in foetal carotid <jats:italic>P<\/jats:italic>CO<jats:sub>2<\/jats:sub> commensurate with that in the maternal blood. In mature lambs (at 0\u00b79 or more of term) the fall in foetal carotid <jats:italic>P<\/jats:italic>CO<jats:sub>2<\/jats:sub> was less than that in maternal blood, whether the foetus was exteriorized or <jats:italic>in utero<\/jats:italic>.<\/jats:p><jats:p>3. The mean transplacental gradient for <jats:italic>P<\/jats:italic>CO<jats:sub>2<\/jats:sub> (maternal arterial\u2010umbilical vascular), when the foetus was replaced with a mechanical pump recirculating foetal blood, was 6\u00b73 mm Hg. This is attributed to placental CO<jats:sub>2<\/jats:sub> production, and is nearly half the mean <jats:italic>P<\/jats:italic>CO<jats:sub>2<\/jats:sub> gradient (maternal artery\u2010foetal carotid) of about 14 mm Hg during normal maternal ventilation.<\/jats:p><jats:p>4. The mean maternal\u2010umbilical transcotyledonary venous gradients (avoiding vascular shunts through the myometrium and intercotyledonary chorion) were for <jats:italic>P<\/jats:italic>CO<jats:sub>2<\/jats:sub> 1\u00b77 mm Hg and for <jats:italic>P<\/jats:italic>O<jats:sub>2<\/jats:sub> 13\u00b74 mm Hg.<\/jats:p><jats:p>5. Maternal hyperventilation (<jats:italic>P<\/jats:italic><jats:sub>a<\/jats:sub>, CO<jats:sub>2<\/jats:sub> \u223c 20 mm Hg) caused a small fall in mean foetal carotid <jats:italic>P<\/jats:italic>O<jats:sub>2<\/jats:sub> (5 mm Hg), which was readily reversible with no evidence of progressive acidaemia.<\/jats:p>","DOI":"10.1113\/jphysiol.1971.sp009637","type":"journal-article","created":{"date-parts":[[2014,12,19]],"date-time":"2014-12-19T11:13:51Z","timestamp":1418987631000},"page":"635-650","source":"Crossref","is-referenced-by-count":9,"title":["Maternal hyperventilation and foetal hypocapnia in sheep"],"prefix":"10.1113","volume":"218","author":[{"given":"P.","family":"Baillie","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"G. S.","family":"Dawes","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claudie L.","family":"Merlet","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"R.","family":"Richards","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[1971,11]]},"container-title":["The Journal of Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1113%2Fjphysiol.1971.sp009637","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/pdf\/10.1113\/jphysiol.1971.sp009637","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,11,8]],"date-time":"2023-11-08T15:02:54Z","timestamp":1699455774000},"score":1,"resource":{"primary":{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/10.1113\/jphysiol.1971.sp009637"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1971,11]]},"references-count":0,"journal-issue":{"issue":"3","published-print":{"date-parts":[[1971,11]]}},"alternative-id":["10.1113\/jphysiol.1971.sp009637"],"URL":"https:\/\/doi.org\/10.1113\/jphysiol.1971.sp009637","archive":["Portico"],"relation":{},"ISSN":["0022-3751","1469-7793"],"issn-type":[{"value":"0022-3751","type":"print"},{"value":"1469-7793","type":"electronic"}],"subject":[],"published":{"date-parts":[[1971,11]]}}}