{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T21:23:49Z","timestamp":1790717029248,"version":"4.1.0"},"reference-count":23,"publisher":"American Physiological Society","issue":"7","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["American Journal of Physiology-Regulatory, Integrative and Comparative Physiology"],"published-print":{"date-parts":[[2014,10,1]]},"abstract":"<jats:p> Facial pallor is commonly observed at presyncope in humans, suggestive of reductions in facial skin blood flow (SkBF). Yet, cutaneous vasoconstriction is usually minimal at presyncope when measured at the forearm. We tested the hypothesis that reductions in forehead SkBF at presyncope are greater than in the forearm. Forehead and forearm SkBF (laser-Doppler) and blood pressure (Finometer or radial artery catheterization) were measured during lower body negative pressure (LBNP) to presyncope in 11 normothermic and 13 heat-stressed subjects (intestinal temperature increased \u223c1.4\u00b0C). LBNP reduced mean arterial pressure from 91 \u00b1 5 to 57 \u00b1 7 mmHg during normothermia ( P \u2264 0.001) and from 82 \u00b1 5 to 57 \u00b1 7 mmHg during heat stress ( P \u2264 0.001). During normothermia, LBNP decreased forehead SkBF 55 \u00b1 14% compared with 24 \u00b1 11% at the forearm ( P = 0.002), while during heat stress LBNP decreased forehead SkBF 39 \u00b1 11% compared with 28 \u00b1 8% in the forearm ( P = 0.007). In both conditions, most (\u226568%) of the decreases in SkBF were due to decreases in blood pressure. However, a greater contribution of actively mediated reductions in SkBF was observed at the forehead, relative to the forearm during normothermia (32 \u00b1 13% vs. 11 \u00b1 11%, P = 0.031) and heat stress (30 \u00b1 13% vs. 10 \u00b1 13%, P = 0.004). These data suggest that facial pallor at presyncope is due to a combination of passive decreases in forehead SkBF secondary to reductions in blood pressure and to active decreases in SkBF, the latter of which are relatively greater than in the forearm. <\/jats:p>","DOI":"10.1152\/ajpregu.00204.2014","type":"journal-article","created":{"date-parts":[[2014,8,7]],"date-time":"2014-08-07T05:51:27Z","timestamp":1407390687000},"page":"R908-R913","source":"Crossref","is-referenced-by-count":10,"title":["Forehead versus forearm skin vascular responses at presyncope in humans"],"prefix":"10.1152","volume":"307","author":[{"given":"Daniel","family":"Gagnon","sequence":"first","affiliation":[{"name":"Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and University of Texas Southwestern Medical Center, Dallas, Texas;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R.","family":"Matthew Brothers","sequence":"additional","affiliation":[{"name":"Environmental and Autonomic Physiology Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, Texas;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matthew S.","family":"Ganio","sequence":"additional","affiliation":[{"name":"Department of Health, Human Performance and Recreation, University of Arkansas, Fayetteville, Arkansas; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeffrey L.","family":"Hastings","sequence":"additional","affiliation":[{"name":"Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and University of Texas Southwestern Medical Center, Dallas, Texas;"},{"name":"Veterans Affairs North Texas Health Care System, Dallas, Texas"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Craig G.","family":"Crandall","sequence":"additional","affiliation":[{"name":"Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas and University of Texas Southwestern Medical Center, Dallas, Texas;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00290.2010"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2004.075747"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.1962.sp006887"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00169.2012"},{"key":"B5","doi-asserted-by":"crossref","first-page":"692","DOI":"10.1152\/ajplegacy.1942.136.4.692","volume":"136","author":"Hertzman AB","year":"1942","journal-title":"Am J Physiol"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1007\/BF00376498"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1007\/s00421-004-1303-2"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.1989.257.5.H1599"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1161\/01.RES.77.6.1222"},{"key":"B10","first-page":"33","volume":"16","author":"Lewis T","year":"1931","journal-title":"Heart"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1111\/j.1475-097X.2012.01137.x"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.1990.sp018020"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00535.2013"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1038\/jcbfm.2013.149"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.01078.2013"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1113\/expphysiol.2013.072082"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1111\/j.1748-1716.1993.tb09518.x"},{"key":"B18","first-page":"67","volume":"16","author":"Roddie IC","year":"1957","journal-title":"Clin Sci"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2006.112649"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2007.144030"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9149(65)90027-5"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1989.66.4.1586"},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.1016\/S1566-0702(02)00046-2"}],"container-title":["American Journal of Physiology-Regulatory, Integrative and Comparative Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.physiology.org\/doi\/pdf\/10.1152\/ajpregu.00204.2014","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,9,8]],"date-time":"2019-09-08T17:32:08Z","timestamp":1567963928000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.physiology.org\/doi\/10.1152\/ajpregu.00204.2014"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,10,1]]},"references-count":23,"journal-issue":{"issue":"7","published-print":{"date-parts":[[2014,10,1]]}},"alternative-id":["10.1152\/ajpregu.00204.2014"],"URL":"https:\/\/doi.org\/10.1152\/ajpregu.00204.2014","relation":{},"ISSN":["0363-6119","1522-1490"],"issn-type":[{"value":"0363-6119","type":"print"},{"value":"1522-1490","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,10,1]]}}}