Abstract: | The effect of synthetic corticosteroids given intratracheally or orally on the adrenal glands of beagle dogs was investigated. The adrenal function was evaluated using a standardized ACTH stimulation test. In addition, histological and morphometrical examinations of the adrenal cortex were performed at the end of the study. Beclomethasone dipropionate given intratracheally at daily dose levels of 0.05, 0.1 and 0.5 mg/kg body weight led to a dose dependent adrenal suppression on the basis of plasma cortisol concentration and eosinophil counts after ACTH stimulation and size of zona fasciculata and reticularis. A complete adrenal suppression was observed at the highest dose level of 0.5 mg/kg body weight. Also the oral administration of 0.1 mg/kg body weight/day of beclomethasone dipropionate had a definite adrenal suppressive effect comparaable to that of 0.1 mg/kg body weight given intratracheally. However, intratracheal administration of fluocortin butylester, a local antiinflammatory drug but systemically a nearly ineffective corticosteroid (2 X 8 mg/kg body weight/day) had no suppressive effect on the adrenal gland of the beagle dog, even after a 320 times higher dose. |