{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T02:33:22Z","timestamp":1783650802832,"version":"3.55.0"},"reference-count":18,"publisher":"American Physiological Society","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["American Journal of Physiology-Regulatory, Integrative and Comparative Physiology"],"published-print":{"date-parts":[[2010,1]]},"abstract":"<jats:p> Recent studies report that the menstrual cycle alters sympathetic neural responses to orthostatic stress in young, eumenorrheic women. The purpose of the present study was to determine whether oral contraceptives (OC) influence sympathetic neural activation during an orthostatic challenge. Based on evidence that sympathetic baroreflex sensitivity (BRS) is increased during the \u201clow hormone\u201d (LH) phase (i.e., placebo pills) in women taking OC, we hypothesized an augmented muscle sympathetic nerve activity (MSNA) response to orthostatic stress during the LH phase. MSNA, mean arterial pressure (MAP), and heart rate (HR) were recorded during progressive lower body negative pressure (LBNP; \u22125, \u221210, \u221215, \u221220, \u221230, \u221240 mmHg; 3 min\/stage) in 12 healthy women taking OC (age 22 \u00b1 1 years). Sympathetic BRS was assessed by examining relations between spontaneous fluctuations of diastolic arterial pressure and MSNA. Subjects were examined twice: once during LH phase and once \u223c3 wk after LH during the \u201chigh hormone\u201d phase (randomized order). Resting MSNA (10 \u00b1 2 vs. 13 \u00b1 2 bursts\/min), MAP (85 \u00b1 3 vs. 84 \u00b1 3 mmHg), and HR (62 \u00b1 2 vs. 65 \u00b1 3 beats\/min) were not different between phases. MSNA and HR increased during progressive LBNP ( P &lt; 0.001), and these increases were similar between phases. Progressive LBNP did not change MAP during either phase. Sympathetic BRS increased during progressive LBNP, but these responses were not different between LH and high hormone phases. In conclusion, our results demonstrate that OCs do not alter cardiovascular and sympathetic neural responses to an orthostatic challenge in young, healthy women. <\/jats:p>","DOI":"10.1152\/ajpregu.00554.2009","type":"journal-article","created":{"date-parts":[[2009,10,15]],"date-time":"2009-10-15T02:15:27Z","timestamp":1255572927000},"page":"R9-R14","source":"Crossref","is-referenced-by-count":36,"title":["Effects of oral contraceptives on sympathetic nerve activity during orthostatic stress in young, healthy women"],"prefix":"10.1152","volume":"298","author":[{"given":"Jason R.","family":"Carter","sequence":"first","affiliation":[{"name":"Department of Exercise Science, Health, and Physical Education, Michigan Technological University, Houghton, Michigan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jenna C.","family":"Klein","sequence":"additional","affiliation":[{"name":"Department of Exercise Science, Health, and Physical Education, Michigan Technological University, Houghton, Michigan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher E.","family":"Schwartz","sequence":"additional","affiliation":[{"name":"Department of Exercise Science, Health, and Physical Education, Michigan Technological University, Houghton, Michigan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2007.141051"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1152\/ajpendo.00019.2009"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1998.85.6.2075"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2008.168468"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2006.117507"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2003.057133"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2006.108662"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-7793.2001.0861h.x"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1152\/ajpendo.00056.2008"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.101.8.862"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.102.13.1473"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00708.2007"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9378(87)90364-4"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.01197.2008"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1161\/01.HYP.19.6.508"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2008.09.042"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.2001.281.4.R1319"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.1978.sp012322"}],"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.00554.2009","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,9,8]],"date-time":"2019-09-08T16:22:21Z","timestamp":1567959741000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.physiology.org\/doi\/10.1152\/ajpregu.00554.2009"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,1]]},"references-count":18,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2010,1]]}},"alternative-id":["10.1152\/ajpregu.00554.2009"],"URL":"https:\/\/doi.org\/10.1152\/ajpregu.00554.2009","relation":{},"ISSN":["0363-6119","1522-1490"],"issn-type":[{"value":"0363-6119","type":"print"},{"value":"1522-1490","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,1]]}}}