EFFECT OF RACE ON BONE DENSITY IN CHILDREN

我们目前对骨质疏松症发病机制的理解是 由于缺乏有关决定因素的信息， 在生长过程中增加的骨量。 自实现 骨骼成熟时更大的骨量可能会降低 在以后的生活中发展骨质疏松症，更好地了解 儿童生长期间骨密度的决定因素， 青春期是必需的。 初步横断面研究 表明骨密度在青春期会急剧增加 无论是男孩还是女孩，在此期间这种上升的程度 黑人的青春期晚于白人。 但 骨密度增加的原因 青春期和机制，占发展 在这个年龄阶段，骨量的种族差异仍然存在 不确定 具体来说，血清中的变化 骨细胞代谢的几种重要调节剂的水平 在青春期，如性类固醇和钙调节 激素是未知的;变化的可能性， 在组织水平上骨对这些重要调节剂的反应 对骨代谢的影响也有待进一步研究。 本建议的目的是更仔细地审查 性类固醇和钙调节激素的作用， 正常青春期骨密度增加的决定因素 成长中的黑人和白色孩子。 以下目标是 划定： 1.为了描述椎体骨密度的变化， 松质骨和皮质骨密度在每个阶段的性 黑人和白色男性和女性的发育。 2 .确定骨密度增加与 性激素和钙的血清水平 调节荷尔蒙 3 .第三章。为了确定青春期前测量脊椎骨是否 骨密度预测骨骼成熟时的骨密度。 4.为了比较骨骼的反应和生长的变化， 黑人和白色儿童雌激素治疗后激素分泌 局

Our current understanding about the pathogenesis of osteoporosis is limited by a lack of information about the factors that determine the amount of bone gained during growth. Since the attainment of greater bone mass at skeletal maturity may reduce the risk of developing osteoporosis later in life, a better understanding of the determinants of bone density during growth in childhood and adolescence is required. Preliminary cross-sectional studies indicate that bone density increases dramatically during puberty both in boys and in girls and that the extent of this rise during late puberty is greater in blacks than in whites. However, the factors responsible for increases in bone density during adolescence and the mechanisms which account for the development of racial differences in bone mass at this time in life remain uncertain. Specifically, the role of alterations in the serum levels of several important modifiers of bone cell metabolism during puberty, such as sex steroids and calcium-regulating hormones is unknown; the possibility that variations in the response of bone at the tissue level to these important regulators of bone metabolism also wan-ants further investigation. It is the purpose of the current proposal to examine more closely the roles of sex steroids and calcium regulating hormones as determinants of the normal pubertal increase in bone density in growing black and white children. The following objectives are delineated: 1. To characterize the changes in vertebral bone density of cancellous and cortical bone density at each stage of sexual development in black and white males and females. 2 .To determine the relationship between increases in bone density during-puberty and the serum levels of sex steroids and calcium regulating hormones. 3 . To determine whether prepubertal measurements of vertebral bone density predict bone density at skeletal maturity. 4. To compare both the response of bone and the change in growth hormone secretion in black and white children after estrogen administration.