| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Departments of 1 Health and Kinesiology and 2 Medical Physiology, and Cardiovascular Research Institute, Texas A&M University, College Station, Texas 77843; 3 Department of Bone and Cartilage Biology, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406; and 4 Department of Orthopaedic Surgery, Mayo Clinic, Rochester, Minnesota 55905
Bone loss occurs as a
consequence of exposure to microgravity. Using the
hindlimb-unloaded rat to model spaceflight, this study had as its
purpose to determine whether skeletal unloading and cephalic fluid
shifts alter bone blood flow. We hypothesized that perfusion would be
diminished in the hindlimb bones and increased in skeletal structures
of the forelimbs and head. Using radiolabeled microspheres, we measured
skeletal perfusion during control standing and after 10 min, 7 days,
and 28 days of hindlimb unloading (HU). Femoral and tibial perfusion
were reduced with 10 min of HU, and blood flow to the femoral shaft and
marrow were further diminished with 28 days of HU. Correspondingly, the
mass of femora (
11%, P < 0.05) and tibiae (6%,
P < 0.1) was lowered with 28 days of HU. In contrast,
blood flow to the skull, mandible, clavicle, and humerus was increased
with 10 min HU but returned to control levels with 7 days HU.
Mandibular (+10%, P < 0.05), clavicular (+18%,
P < 0.05), and humeral (+8%, P < 0.1) mass was increased with chronic HU. The data demonstrate that
simulated microgravity alters bone perfusion and that such alterations
correspond to unloading-induced changes in bone mass. These results
support the hypothesis that alterations in bone blood flow provide a
stimulus for bone remodeling during periods of microgravity.
bone blood flow; hindlimb unloading; vascular resistance
This article has been cited by other articles:
|
|
 |
|
  K. A. Radek, L. A. Baer, J. Eckhardt, L. A. DiPietro, and C. E. Wade Mechanical unloading impairs keratinocyte migration and angiogenesis during cutaneous wound healing J Appl Physiol, May 1, 2008; 104(5): 1295 - 1303. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Ishijima, K. Tsuji, S. R Rittling, T. Yamashita, H. Kurosawa, D. T Denhardt, A. Nifuji, Y. Ezura, and M. Noda Osteopontin is required for mechanical stress-dependent signals to bone marrow cells J. Endocrinol., May 1, 2007; 193(2): 235 - 243. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Hwang, S. A. Shelkovnikov, and R. E. Purdy Simulated microgravity effects on the rat carotid and femoral arteries: role of contractile protein expression and mechanical properties of the vessel wall J Appl Physiol, April 1, 2007; 102(4): 1595 - 1603. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. C. Tuday, J. V. Meck, D. Nyhan, A. A. Shoukas, and D. E. Berkowitz Microgravity-induced changes in aortic stiffness and their role in orthostatic intolerance J Appl Physiol, March 1, 2007; 102(3): 853 - 858. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Rittweger, K. Winwood, O. Seynnes, M. de Boer, D. Wilks, R. Lea, M. Rennie, and M. Narici Bone loss from the human distal tibia epiphysis during 24 days of unilateral lower limb suspension J. Physiol., November 15, 2006; 577(1): 331 - 337. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. J. Somerman and L. K. McCauley Bisphosphonates: Sacrificing the Jaw to Save the Skeleton? IBMS BoneKEy, September 1, 2006; 3(9): 12 - 18. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. A. Gashev, M. D. Delp, and D. C. Zawieja Inhibition of active lymph pump by simulated microgravity in rats Am J Physiol Heart Circ Physiol, June 1, 2006; 290(6): H2295 - H2308. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. W. Zderic and M. T. Hamilton Physical inactivity amplifies the sensitivity of skeletal muscle to the lipid-induced downregulation of lipoprotein lipase activity J Appl Physiol, January 1, 2006; 100(1): 249 - 257. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. G. Lentle and M. C. Kruger Changes in mineralization and biomechanics of tibial metaphyses in splinted rats J Appl Physiol, July 1, 2005; 99(1): 173 - 180. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. J. Mueller, C. M. Foley, and E. M. Hasser Hindlimb unloading alters nitric oxide and autonomic control of resting arterial pressure in conscious rats Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2005; 289(1): R140 - R147. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. M. Stewart, C. Karman, L. D. Montgomery, and K. J. McLeod Plantar vibration improves leg fluid flow in perimenopausal women Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2005; 288(3): R623 - R629. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Sun, L.-F. Zhang, F. Gao, X.-W. Ma, M.-L. Zhang, J. Liu, L.-N. Zhang, and J. Ma Daily short-period gravitation can prevent functional and structural changes in arteries of simulated microgravity rats J Appl Physiol, September 1, 2004; 97(3): 1022 - 1031. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. M. Smith, J. E. Davis-Street, J. V. Fesperman, M. D. Smith, B. L. Rice, and S. R. Zwart Nutritional Status Changes in Humans during a 14-Day Saturation Dive: The NASA Extreme Environment Mission Operations V Project J. Nutr., July 1, 2004; 134(7): 1765 - 1771. [Abstract] [Full Text]
|
|
|
|
|
|
D. W. Stepp, D. M. Pollock, and J. C. Frisbee Low-flow vascular remodeling in the metabolic syndrome X Am J Physiol Heart Circ Physiol, March 1, 2004; 286(3): H964 - H970. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Papadopoulos and M. D. Delp Effects of hindlimb unweighting on the mechanical and structure properties of the rat abdominal aorta J Appl Physiol, February 1, 2003; 94(2): 439 - 445. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Ma, C. I. Kahwaji, Z. Ni, N. D. Vaziri, and R. E. Purdy Effects of simulated microgravity on arterial nitric oxide synthase and nitrate and nitrite content J Appl Physiol, January 1, 2003; 94(1): 83 - 92. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Nyhan, S. Kim, S. Dunbar, D. Li, A. Shoukas, and D. E. Berkowitz Impaired pulmonary artery contractile responses in a rat model of microgravity: role of nitric oxide J Appl Physiol, January 1, 2002; 92(1): 33 - 40. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. K. Wilkerson, P. N. Colleran, and M. D. Delp Acute and chronic head-down tail suspension diminishes cerebral perfusion in rats Am J Physiol Heart Circ Physiol, January 1, 2002; 282(1): H328 - H334. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L.-F. Zhang Vascular adaptation to microgravity: what have we learned? J Appl Physiol, December 1, 2001; 91(6): 2415 - 2430. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. A. Ray, M. Vasques, T. A. Miller, M. K. Wilkerson, and M. D. Delp Effect of short-term microgravity and long-term hindlimb unloading on rat cardiac mass and function J Appl Physiol, September 1, 2001; 91(3): 1207 - 1213. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
