Patterson-Buckendahl P, Rusnák M, Fukuhara K, Kvetnanský R
Center of Alcohol Studies, Rutgers University, Piscataway, New Jersey 08854, USA.
Am J Physiol Regul Integr Comp Physiol. 2001 Jan;280(1):R79-86. doi: 10.1152/ajpregu.2001.280.1.R79.
We previously showed that psychological stressors alter plasma levels of osteocalcin (pOC), a bone-specific mineral binding protein, in ways that differ with the type of stressor. To determine effects of chronic stress, we examined vertebrae, pOC, and corticosterone levels from conscious rats subjected to foot-restraint immobilization (Immo) daily for 1-42 times. After 40-42 Immo, basal pOC was decreased by 25% compared with unstressed rats, and the subsequent rise in pOC during Immo was blunted. Corticosterone was elevated 10-fold during Immo. Immo for seven times did not change vertebral OC concentration, but caused a slight decrease in calcium and phosphorous concentrations in younger rats. Rats Immo for 42 times exhibited reduced body weight, vertebral weight, and vertebral OC concentration but no significant differences in vertebral mineral concentrations. Body fat content was visibly decreased. We do not know the source of or the stimulus for the initial rise in pOC. We conclude that both decreased growth and bone OC concentration are due to repeatedly elevated stress hormones.
我们之前表明，心理应激源会改变骨钙素（pOC，一种骨特异性矿物质结合蛋白）的血浆水平，其改变方式因应激源类型而异。为了确定慢性应激的影响，我们检测了每天接受1 - 42次足部束缚制动（Immo）的清醒大鼠的椎骨、pOC和皮质酮水平。在40 - 42次Immo后，与未受应激的大鼠相比，基础pOC降低了25%，并且在Immo期间pOC随后的升高受到抑制。皮质酮在Immo期间升高了10倍。7次Immo并未改变椎骨OC浓度，但导致幼龄大鼠钙和磷浓度略有降低。接受42次Immo的大鼠体重、椎骨重量和椎骨OC浓度降低，但椎骨矿物质浓度无显著差异。体脂含量明显降低。我们不知道pOC最初升高的来源或刺激因素。我们得出结论，生长和骨OC浓度降低均归因于应激激素反复升高。
