Summary
Effects of androgen deficiency and androgen replacement on bone density, as measured with dual-energy X-ray absorptiometry (DXA) and single photon absorptiometry (SPA), cortical ratio (cortical thickness/outside bone diameter x 100), and biomechanical properties were evaluated in 14-month-old (1 month after orchiectomy (orch) or sham-operation) and in 17-month-old (4 months after orch or sham) male rats. Whole femoral bone mineral content (BMC) and density (BMD) measured with DXA were not significantly decreased 1 month after orch. Whole femoral BMC and BMD were 10% and 8% lower in 4 months after orch (P < 0.01 andP < 0.001, respectively). This decrease was prevented by testosterone replacement. There was an excellent correlation (R = 0.99) between whole femoral BMC and femoral ash weight. Selective scanning of cortical and cancellous sites of the femur showed that both cancellous and cortical BMC and BMD were significantly decreased 4 months after orch. SPA of the right tibia confirmed a 7% decrease in cancellous BMC and BMD 4 months after orch (preventable by testosterone) but not in cortical BMD and BMC. Femoral cortical ratio decreased with age (47 ± 2 in 14-month-old and 40 ± 2 in 17-month-old sham rats versus 63 ± 1 in 6-month-old male rats) due to a continuously enlarging femoral shaft. Androgen deficiency resulted in an even greater decrease of the cortical ratio 4 months after orch (36 ± 2 in 17-month-old orch rats) that was again prevented by testosterone (47 ± 3). These changes in femoral cortical, cancellous density, and cortical ratio did not affect biomechanical properties of the femur as evaluated by torsion testing. The lack of an effect on bone biomechanics was most likely due to the protection afforded by an increased femoral shaft diameter. We conclude that 4 months after orch, aged male orch rats had a lower femoral cortical and cancellous density and a lower cortical ratio without decrease of biomechanical properties of the femoral shaft. Testosterone replacement was effective not only in preventing the decrease of cancellous and cortical density but also in preventing the age-related thinning of the femoral cortex.
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References
Anderson DC (1992) Osteoporosis in men. Br Med J 305:489–490
Greenspan SL, Neer RM, Ridgway EG, Klibanski A (1986) Osteoporosis in men with hyperprolactinemic hypogonadism. Ann Intern Med 110:526–531
Finkelstein DJ, Klibanski A, Neer RM, Doppelt SM, Rosenthal DI, Segre GV, Crowley WH (1989) Increases in bone density during treatment of men with idiopathic hypogonadotropic hypogonadism. J Clin Endocrinol Metab 69:776–783
Seeman E, Melton LJ, O'Fallon WM, Riggs BL (1983) Risk factors for spinal osteoporosis in men. Am J Med 75:977–983
Johansen JS, Giwercman A, Hartwell D, Nielsen CT, Price PA, Christiansen C, Skakkabaek NE (1988) Serum bone gla-protein as a marker of bone growth in children and adolescents: correlation with age, height, serum insulin-like growth factor I and serum testosterone. J Clin Endocrinol Metab 67:273–278
Finkelstein JS, Neer RM, Billen BMK, Crawford JD, Kilanski A (1992) Osteopenia in men with a history of delayed puberty. N Engl J Med 326:600–604
Riggs BL, Melton LJ III (1986) Involutional osteoporosis. N Engl J Med 314:1676–1686
Vanderschueren D, Van Herck E, Suiker AMH, Visser WJ, Schot LPC, Bouillon R (1992) Bone and mineral metabolism in aged male rats: short- and long-term effects of androgen deficiency. Endocrinology 130:2906–2916
Stefan JJ, Lachman M, Zverina J, Pacovsky V, Baylink DJ (1989) Castrated men exhibit bone loss: effect of calcitonin treatment on biochemical indices of bone remodeling. J Clin Endocrinol Metab 69:523–527
Vermeulen A (1990) Androgens and male senescence. In: Nieschlag E, Behre NM (eds) Testosterone: action, deficiency, substitution. Springer Verlag, Heidelberg, pp 261–276
Foresta C, Ruzza G, Mioni R, Guarneri G, Gribaldo R, Meneghello A, Mastrogiacomo I (1984) Osteoporosis and decline of gonadal function in the elderly male. Horm Res 0:18–22
Geusens P, Dequeker J, Nijs J, Bramm E (1990) Effect of ovariectomy and prednisolone on bone mineral content in rats: evaluation by single photon absorptiometry and radiogrammetry. Calcif Tissue Int 47:243–250
Amman P, Rizolli R, Slosman D, Bonjour JP (1992) Sequential and precise in vivo measurement of bone mineral density in rats using dual-energy x-ray absorptiometry. J Bone Miner Res 7:311–316
Frost HM (1985) The pathomechanics of osteoporosis. Clin Orthop Rel Res 200:198–224
Schoutens A, Verhas M, L'Hermite-Baleriaux M, L'Hermite M, Verschaeren A, Dourov N, Mone M, Heilporn A, Tricot A (1984) Growth and bone haemodynamic responses to castration in male rats. Reversibility by testosterone. Acta Endocrinol 107:428–432
Wakley GK, Schritte HD, Kathleen SH, Turner RT (1991) Androgen treatment prevents loss of cancellous bone in the orchidectomized rat. J Bone Miner Res 6:325–330
Saville PD (1969) Changes in skeletal mass and fragility with castration in the rat: a model for osteoporosis. J Am Geriatr Soc 17:155–166
Hock JM, Fonseca J, Gunness-Hey, Kemp BE, Martin TJ (1989) Comparison of the anabolic effects of synthetic parathyroid hormone-related protein (PTHrP)1-34 and PTH 1-34 on bone in rats. Endocrinology 125:2022–2027
Wink CS, Felts WJL (1980) Effects of castration on the bone structure of male rats: a model for osteoporosis. Calcif Tissue Int 32:77–82
Verhas M, Schoutens A, L'Hermite-Baleriaux M, Dourov N, Verschaeren A, Mone M, Heilporn A (1986) The effect of orchidectomy on bone metabolism in aging rats. Calcif Tissue Int 39:74–77
Kimmel DB, Wronski TJ (1990) Nondestructive measurement of bone mineral in femurs from ovariectomized rats. Calcif Tissue Int 46:101–110
Tran Van P, Vignery A, Baron R (1982) Cellular kinetics of the bone remodeling sequence in the rat. Anat Rec 202:445–451
Vanderschueren D, Van Herck E, Suiker AMH, Allewaert K, Visser WJ, Geusens P, Bouillon R (1992) Bone and mineral metabolism in the adult guinea pig: long-term effects of estrogen and androgen deficiency. J Bone Miner Res 7:1407–1415
Geusens P, Dequeker J, Verstraeten A, Nijs J (1986) Age-, sex-, and menopause-related changes of vertebral and peripheral bone: population study using dual and single photon absorptiometry and radiogrammatry. J Nucl Med 27:1540–1549
Martin RK, Albright JP, Jee WSS, Taylor GN, Clarke WR (1981) Bone loss in the beagle tibia: influence of age, weight and sex. Calcif Tissue Int 33:233–238
Danielson CC, Mosekilde L, Andreassen TT (1992) Long-term effect of orchidectomy on cortical bone from rat femur: bone mass and mechanical properties. Calcif Tissue Int 50:169–174
Martin RB, Atkinson PJ (1977) Age- and sex-related changes in the structure and strength of the human femoral shaft. J Biomech 10:223–231
Stanley HL, Schmitt BP, Poses RM, Deis WP (1991) Does hypogonadism contribute to the occurrence of a minimal trauma hip fracture in elderly men. J Am Geriat Soc 0:766–771
Ruff CB, Hayes WC (1982) Subpereostal expansion and cortical remodeling of the human femur and tibia with aging. Science 217:945–948
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Vanderschueren, D., Van Herck, E., Schot, P. et al. The aged male rat as a model for human osteoporosis: Evaluation by nondestructive measurements and biomechanical testing. Calcif Tissue Int 53, 342–347 (1993). https://doi.org/10.1007/BF01351841
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DOI: https://doi.org/10.1007/BF01351841