{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T20:05:44Z","timestamp":1787169944272,"version":"build-2736575974"},"reference-count":29,"publisher":"American Physiological Society","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["American Journal of Physiology-Heart and Circulatory Physiology"],"published-print":{"date-parts":[[2008,9]]},"abstract":"<jats:p>We hypothesized that exposure to prolonged recumbency (bedrest), and thus reductions of intravascular pressure gradients, increases pressure distension in arteries\/arterioles in the legs. Ten subjects underwent 5 wk of horizontal bedrest. Pressure distension was investigated in arteries and arterioles before and after the bedrest, with the subject seated or supine in a hyperbaric chamber with either one arm or a lower leg protruding through a hole in the chamber door. Increased pressure in the vessels of the arm\/leg was accomplished by increasing chamber pressure. Vessel diameter and flow were measured in the brachial and posterior tibial arteries using Doppler ultrasonography. Electrical tissue impedance was measured in the test limb. Bedrest increased ( P &lt; 0.01) pressure distension threefold in the tibial artery (from 8 \u00b1 7% to 24 \u00b1 11%) and by a third ( P &lt; 0.05) in the brachial artery (from 15 \u00b1 9% to 20 \u00b1 10%). The pressure-induced increase in tibial artery flow was more pronounced ( P &lt; 0.01) after (50 \u00b1 39 ml\/min) than before (13 \u00b1 23 ml\/min) bedrest, whereas the brachial artery flow response was unaffected by bedrest. The pressure-induced decrease in tissue impedance in the leg was more pronounced ( P &lt; 0.01) after (16 \u00b1 7%) than before (10 \u00b1 6%) bedrest, whereas bedrest did not affect the impedance response in the arm. Thus, withdrawal of the hydrostatic pressure gradients that act along the blood vessels in erect posture markedly increases pressure distension in dependent arteries and arterioles.<\/jats:p>","DOI":"10.1152\/ajpheart.00576.2008","type":"journal-article","created":{"date-parts":[[2008,7,25]],"date-time":"2008-07-25T21:09:33Z","timestamp":1217020173000},"page":"H1296-H1302","source":"Crossref","is-referenced-by-count":22,"title":["Pressure-distension relationship in arteries and arterioles in response to 5 wk of horizontal bedrest"],"prefix":"10.1152","volume":"295","author":[{"given":"Ola","family":"Eiken","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roger","family":"K\u00f6leg\u00e5rd","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Igor B.","family":"Mekjavic","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"R1","doi-asserted-by":"publisher","DOI":"10.1007\/s00421-006-0346-y"},{"key":"R2","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00118.2005"},{"key":"R3","unstructured":"Blomqvist CG\n                      , Stone HL.\n                      Cardiovascular adjustments to gravitational stress. In:\n                      Handbook of Physiology. The Cardiovascular System. Peripheral Circulation and Organ Blood Flow\n                      . Bethesda, MD: Am. Physiol. Soc. 1983, sect. 2, vol. III, pt. 2, chapt. 28, p. 1025\u20131063."},{"key":"R4","doi-asserted-by":"publisher","DOI":"10.1249\/00005768-198205000-00012"},{"key":"R5","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1996.81.1.7"},{"key":"R6","doi-asserted-by":"publisher","DOI":"10.1097\/00005768-199710000-00005"},{"key":"R7","doi-asserted-by":"publisher","DOI":"10.1042\/cs1030221"},{"key":"R8","doi-asserted-by":"publisher","DOI":"10.1249\/00003677-199001000-00007"},{"key":"R9","doi-asserted-by":"publisher","DOI":"10.1016\/j.actaastro.2006.08.007"},{"key":"R10","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.2000.278.6.H1866"},{"key":"R11","unstructured":"Eiken O\n                      , K\u00f6leg\u00e5rd R.\n                      Pain in the arms induced by markedly increased intravascular pressure decreases after repeated exposures to moderately increased pressures.\n                      J Gravit Phyiol\n                      6\n                      : 35\u201336, 1999."},{"key":"R12","unstructured":"Eiken O\n                      , K\u00f6leg\u00e5rd R.\n                      Relationship between arm pain and distension of arteries and veins caused by elevation of transmural pressure in local vascular segments.\n                      Aviat Space Environ Med\n                      72\n                      : 427\u2013431, 2001."},{"key":"R13","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-201X.2004.01291.x"},{"key":"R14","doi-asserted-by":"crossref","unstructured":"Folkow B\n                      .\n                      \u201cStructural factor\u201d in primary and secondary hypertension.\n                      Hypertension\n                      16\n                      : 189\u2013101, 1990.","DOI":"10.1161\/01.HYP.16.1.89"},{"key":"R15","unstructured":"Fortney SM\n                      , Schneider VS, Greenleaf JE.\n                      The physiology of bed rest. In:\n                      Handbook of Physiology. Environmental Physiology\n                      . Bethesda, MD: Am. Physiol. Soc. 1996, sect. 4, vol. II, chapt. 39, p. 889\u2013939."},{"key":"R16","unstructured":"Greenleaf JE\n                      , Van Beaumont W, Bernauer EM, Haines RF, Sandler H, Staly RW, Young HL, Yusken JW.\n                      Effects of rehydration on +Gz tolerance after 14 days bed rest.\n                      Aerospace Med\n                      44\n                      : 715\u2013722, 1973."},{"key":"R17","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1999.87.4.1476"},{"key":"R18","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.96.2.517"},{"key":"R19","unstructured":"Linnarsson D\n                      , Tedner B, Eiken O.\n                      Effects of gravity on the fluid balance and distribution in man.\n                      The Physiologist\n                      28\n                      : 28\u201329, 1985."},{"key":"R20","unstructured":"Ma J\n                      , Zhang L, Yu ZB.\n                      Effects of 14-day tail suspension on vasoreactivity of arteries from different parts of the body in rats.\n                      J Gravit Physiol\n                      3\n                      : 9\u201310, 1996."},{"key":"R21","doi-asserted-by":"publisher","DOI":"10.1016\/S0079-6107(02)00052-4"},{"key":"R22","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.38.1.1"},{"key":"R23","unstructured":"Savilov AA\n                      , Lobachgik VI, Babin AM.\n                      Cardiovascular function of man exposed to LBNP tests.\n                      The Physiologist\n                      33\n                      : S128\u2013S132, 1990."},{"key":"R24","doi-asserted-by":"publisher","DOI":"10.1046\/j.1365-2281.1999.00145.x"},{"key":"R25","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1998.84.5.1756"},{"key":"R26","doi-asserted-by":"publisher","DOI":"10.1007\/s004210050299"},{"key":"R27","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.2000.89.1.338"},{"key":"R28","unstructured":"Wijnen JA\n                      , Kuipers H, Kool MJ, Hoeks AP, van Baak MA, Struyker Boudier HA, Verstappen FT, Van Bortel LM.\n                      Vessel wall properties of large arteries in trained and sedentary subjects.\n                      Bas Res Cardiol\n                      86\n                      ,\n                      Suppl\n                      1: 25\u201329, 1991."},{"key":"R29","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.2001.91.6.2415"}],"container-title":["American Journal of Physiology-Heart and Circulatory Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.physiology.org\/doi\/pdf\/10.1152\/ajpheart.00576.2008","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,9,8]],"date-time":"2019-09-08T17:08:32Z","timestamp":1567962512000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.physiology.org\/doi\/10.1152\/ajpheart.00576.2008"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2008,9]]},"references-count":29,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2008,9]]}},"alternative-id":["10.1152\/ajpheart.00576.2008"],"URL":"https:\/\/doi.org\/10.1152\/ajpheart.00576.2008","relation":{},"ISSN":["0363-6135","1522-1539"],"issn-type":[{"value":"0363-6135","type":"print"},{"value":"1522-1539","type":"electronic"}],"subject":[],"published":{"date-parts":[[2008,9]]}}}