TY - JOUR
T1 - Reduced bone perfusion in osteoporosis
T2 - Likely causes in an ovariectomy rat model
AU - Griffith, James F.
AU - Wang, Yi Xiang J
AU - Zhou, Hua
AU - Kwong, Wing Hang
AU - Wong, Wing Tak
AU - Sun, Yan Lin
AU - Huang, Yu
AU - Yeung, David K W
AU - Qin, Ling
AU - Ahuja, Anil T.
PY - 2010/3
Y1 - 2010/3
N2 - Purpose: To investigate the cause of reduced vertebral perfusion in a rat ovariectomy model. Materials and Methods: Experimental protocol was approved by the local Animal Experiment Ethics Committee. Twenty-two Sprague-Dawley rats were studied. Computed tomographic bone densitometry and magnetic resonance perfusion imaging were performed at baseline and 2, 4, and 8 weeks after ovariectomy (n = 11) or sham surgery (n = 11). Perfusion parameters analyzed were maximum enhancement (E max) and enhancement slope (E slope). After the animals were sacrificed, the aorta and femoral artery were analyzed for vessel reactivity, and the lumbar vertebrae were analyzed for marrow content. Results: In control rats, bone mineral density (BMD), Emax, and Eslope remained constant. In ovariectomy rats, a comparable reduction in BMD and the perfusion parameters at two weeks post-ovariectomy (BMD, 9.3%;Emax, 11.6%;Eslope, 9%) was seen 2 weeks after ovariectomy, and further reductions were seen 4 weeks (BMD, 17.5%;Emax, 15.6%; Eslope, 33%) and 8 weeks (BMD, 18.8%;Emax, 14.2%;Eslope, 33%) after ovariectomy. Endothelial dysfunction was observed in both the aorta and femoral artery of the ovariectomy group but not of the control group. Increased marrow fat area was seen in the ovariectomy group (52.9% vs 21.6%;P <.01) owing to an increase in fat cell number. Decreased erythropoetic marrow area (32.5% vs 48.6%; P <.05) was also observed in the ovariectomy group. Conclusion:Reduced bone perfusion occurs in synchrony with reduced BMD. The most likely causes of reduced bone perfusion are a reduction in the amount of erythropoetic marrow and endothelial dysfunction after ovariectomy.
AB - Purpose: To investigate the cause of reduced vertebral perfusion in a rat ovariectomy model. Materials and Methods: Experimental protocol was approved by the local Animal Experiment Ethics Committee. Twenty-two Sprague-Dawley rats were studied. Computed tomographic bone densitometry and magnetic resonance perfusion imaging were performed at baseline and 2, 4, and 8 weeks after ovariectomy (n = 11) or sham surgery (n = 11). Perfusion parameters analyzed were maximum enhancement (E max) and enhancement slope (E slope). After the animals were sacrificed, the aorta and femoral artery were analyzed for vessel reactivity, and the lumbar vertebrae were analyzed for marrow content. Results: In control rats, bone mineral density (BMD), Emax, and Eslope remained constant. In ovariectomy rats, a comparable reduction in BMD and the perfusion parameters at two weeks post-ovariectomy (BMD, 9.3%;Emax, 11.6%;Eslope, 9%) was seen 2 weeks after ovariectomy, and further reductions were seen 4 weeks (BMD, 17.5%;Emax, 15.6%; Eslope, 33%) and 8 weeks (BMD, 18.8%;Emax, 14.2%;Eslope, 33%) after ovariectomy. Endothelial dysfunction was observed in both the aorta and femoral artery of the ovariectomy group but not of the control group. Increased marrow fat area was seen in the ovariectomy group (52.9% vs 21.6%;P <.01) owing to an increase in fat cell number. Decreased erythropoetic marrow area (32.5% vs 48.6%; P <.05) was also observed in the ovariectomy group. Conclusion:Reduced bone perfusion occurs in synchrony with reduced BMD. The most likely causes of reduced bone perfusion are a reduction in the amount of erythropoetic marrow and endothelial dysfunction after ovariectomy.
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U2 - 10.1148/radiol.09090608
DO - 10.1148/radiol.09090608
M3 - Article
C2 - 20177089
AN - SCOPUS:77950143209
VL - 254
SP - 739
EP - 746
JO - Radiology
JF - Radiology
SN - 0033-8419
IS - 3
ER -