Kilpatrick Scott, Gow Adam G, Evans Helen, Mellanby Richard J
Royal (Dick) School of Veterinary Studies, Division of Veterinary Clinical Sciences, Hospital for Small Animals, The University of Edinburgh, Midlothian EH25 9RG, UK.
Roslin Institute, Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Midlothian EH25 9RG, UK.
Res Vet Sci. 2015 Feb;98:13-5. doi: 10.1016/j.rvsc.2014.11.018. Epub 2014 Dec 3.
Dogs with spontaneous disorders of glucocorticoid production often have marked disturbances in calcium homeostasis. For example, hypercalcaemia is frequently observed in dogs with hypoadrenocorticism and secondary hyperparathyroidism is a common feature of canine hyperadrenocorticism. The mechanism(s) by which glucocorticoids modulate calcium homeostasis in dogs remains ill-defined. The hypothesis of this study is that a marked increase in serum cortisol concentrations would lead to an immediate negative calcium balance state which would drive a compensatory increase in parathyroid hormone (PTH) concentrations. This hypothesis was investigated by measuring serum cortisol and plasma PTH concentration in 19 dogs before and after administration of adrenocorticotrophic (ACTH) hormone. Post ACTH administration, there was a significant increase in serum cortisol, but not PTH, concentrations. The results of this study do not support the hypothesis that an increase in endogenous glucocorticoids influences calcium balance sufficiently to cause an immediate, compensatory increase in parathyroid hormone concentration.
患有自发性糖皮质激素分泌紊乱的犬类通常在钙稳态方面存在明显紊乱。例如，低肾上腺皮质功能减退的犬类经常出现高钙血症，而继发性甲状旁腺功能亢进是犬类肾上腺皮质功能亢进的常见特征。糖皮质激素调节犬类钙稳态的机制仍不明确。本研究的假设是，血清皮质醇浓度的显著升高会导致立即出现负钙平衡状态，进而促使甲状旁腺激素（PTH）浓度代偿性增加。通过测量19只犬在注射促肾上腺皮质激素（ACTH）前后的血清皮质醇和血浆PTH浓度来研究这一假设。注射ACTH后，血清皮质醇浓度显著升高，但PTH浓度未升高。本研究结果不支持内源性糖皮质激素增加足以影响钙平衡并导致甲状旁腺激素浓度立即代偿性增加这一假设。
