Histological evaluation of the adrenal glands of seven dogs with hyperadrenocorticism treated with trilostane

Vet Rec. 2007 Feb 17;160(7):219-24. doi: 10.1136/vr.160.7.219.


The lesions in the adrenal glands of seven dogs with hyperadrenocorticism that had been treated with trilostane were studied histologically. The glands of the six dogs with pituitary-dependent hyperadrenocorticism had moderate to severe cortical hyperplasia that was either diffuse or nodular. The lesions were more pronounced in the zona fasciculata than in the zona reticularis, and the zona glomerulosa was normal. In the dog with a functional adrenal tumour the non-tumour bearing adrenal gland showed mild nodular hyperplasia. Five of the seven dogs had variable degrees of adrenal necrosis, which was severe in two of them. The terminal deoxynucleotidyl transferase-mediated DUTP nick-end labelling (TUNEL) reaction specified areas of cell death as apoptosis in three of the dogs, and was positive in one of the dogs without visible areas of cell death. There were variable degrees of cortical haemorrhage in three of the dogs. In some of the dogs the lesions were severe enough to lead to hypoadrenocorticism.

Publication types

  • Case Reports

MeSH terms

  • Adrenal Glands / pathology*
  • Adrenocortical Hyperfunction / drug therapy
  • Adrenocortical Hyperfunction / pathology
  • Adrenocortical Hyperfunction / veterinary*
  • Adrenocorticotropic Hormone / pharmacology
  • Animals
  • Apoptosis
  • Dihydrotestosterone / analogs & derivatives*
  • Dihydrotestosterone / therapeutic use
  • Dog Diseases / drug therapy
  • Dog Diseases / pathology*
  • Dogs
  • Dose-Response Relationship, Drug
  • Enzyme Inhibitors / therapeutic use*
  • Female
  • Hydrocortisone / blood
  • In Situ Nick-End Labeling / methods
  • In Situ Nick-End Labeling / veterinary
  • Male
  • Treatment Outcome


  • Enzyme Inhibitors
  • Dihydrotestosterone
  • Adrenocorticotropic Hormone
  • trilostane
  • Hydrocortisone