2017 ACVIM Forum Research Abstract Program

Feline GH-secreting adenomas expressed SSTRs are similar to human GH-secreting adenomas, having higher SSTR1, SSTR2 and SSTR5 expression than SSTR3 and SSTR4. However, the higher expression of SSTR1 and SSTR5 vs SSTR2 than in most humans may explain the greater biochemical response to pasireotide than octreotide. Decreased D2R expression in larger tumours may be a mechanism allowing unchecked adenoma growth. The receptor expression profiles of feline GH-secreting adenomas will help the search for improved medical management options of feline hypersomatotropism. The ACTH stimulation test, using cosyntropin at 5 mcg/kg IV, is the preferred method for diagnosis of hypoadrenocorticism. Previous studies have shown maximal stimulation of the adrenal glands using 1 mcg/kg cosyntropin in normal dogs. No studies have evaluated the efficacy of the lower dose in dogs suspected of hypoadrenocorticism. Our objective was to compare 1 mcg/kg (low-dose) to 5 mcg/kg (high-dose) cosyntropin IV to determine if both doses result in a similar adrenocortical response.