Rush B R, Worster A A, Flaminio M J, Matson C J, Hakala J E
Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan 66506-5606, USA.
Am J Vet Res. 1998 Aug;59(8):1044-7.
To determine alteration in adrenocortical function in horses with recurrent airway obstruction (heaves) after aerosol and parenteral administration of beclomethasone dipropionate and dexamethasone, respectively.
6 horses with inducible and reversible heaves.
Episodes of heaves were induced by exposure to moldy hay and straw for 7 days (natural challenge). Horses then underwent treatment (aerosolized beclomethasone, parenterally administered dexamethasone, and aerosolized propellant) for 7 days. Horses remained in the mold-contaminated environment for 7 days after discontinuation of drugs. Adrenocortical function was determine by serial evaluation of cortisol concentration in serum obtained on days 0, 7, 9, 12, 14, 16, 19, and 21. Adrenocorticotropic hormone stimulation testing was performed in 4 horses/treatment group on days 0, 7, 14, and 21.
Endogenous cortisol production was suppressed in beclomethasone- and dexamethasone-treated horses within 2 days of treatment but recovered to values similar to those in propellant-treated horses approximately 2 and 4 days after discontinuation of drugs. Serum cortisol concentration in propellant-treated horses gradually decreased during the study and was significantly lower than baseline on days 14, 16, 19, and 21. Mean increase in serum cortisol concentration in response to ACTH stimulation testing after beclomethasone and dexamethasone administration did not differ significantly from the response observed in propellant-treated horses.
Aerosol and parenteral administration of beclomethasone and dexamethasone, respectively, suppressed adrenocortical function; however, endogenous cortisol production resumed approximately 2 and 4 days after discontinuation of drugs. Responsiveness to ACTH stimulation testing was not affected by the 7-day treatment period.
分别通过气雾剂和肠胃外途径给予二丙酸倍氯米松和地塞米松，以确定患有复发性气道阻塞（气喘）的马匹肾上腺皮质功能的变化。
6匹可诱导且可逆性气喘的马。
通过让马匹接触发霉的干草和稻草7天（自然激发）来诱发气喘发作。然后，马匹接受为期7天的治疗（雾化二丙酸倍氯米松、肠胃外给予地塞米松以及雾化推进剂）。停药后，马匹在受霉菌污染的环境中再停留7天。通过连续评估在第0、7、9、12、14、16、19和21天采集的血清中皮质醇浓度来确定肾上腺皮质功能。在第0、7、14和21天，对每个治疗组的4匹马进行促肾上腺皮质激素刺激试验。
在治疗的2天内，接受二丙酸倍氯米松和地塞米松治疗的马匹内源性皮质醇分泌受到抑制，但在停药后约2天和4天恢复到与接受推进剂治疗的马匹相似的值。在研究期间，接受推进剂治疗的马匹血清皮质醇浓度逐渐降低，在第14、16、19和21天显著低于基线水平。给予二丙酸倍氯米松和地塞米松后，促肾上腺皮质激素刺激试验引起的血清皮质醇浓度平均升高与接受推进剂治疗的马匹相比无显著差异。
分别通过气雾剂和肠胃外途径给予二丙酸倍氯米松和地塞米松会抑制肾上腺皮质功能；然而，停药后约2天和4天内源性皮质醇分泌恢复。7天的治疗期未影响对促肾上腺皮质激素刺激试验的反应性。
