This work was conducted at the VCA West Los Angeles Animal Hospital
Comparison of Intravenous versus Intramuscular Administration of Corticotropin-Releasing Hormone in Healthy Cats
Article first published online: 10 MAR 2013
Copyright © 2013 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 27, Issue 3, pages 516–521, May/June 2013
How to Cite
Eiler, K.C., Bruyette, D.S., Behrend, E.N., Kemppainen, R.J. and Kass, P.H. (2013), Comparison of Intravenous versus Intramuscular Administration of Corticotropin-Releasing Hormone in Healthy Cats. Journal of Veterinary Internal Medicine, 27: 516–521. doi: 10.1111/jvim.12054
- Issue published online: 9 MAY 2013
- Article first published online: 10 MAR 2013
- Manuscript Accepted: 21 JAN 2013
- Manuscript Revised: 22 OCT 2012
- Manuscript Received: 11 JUL 2012
- Veterinary Centers of America
- ACTH ;
Because of the lack of a current validated assay for feline endogenous adrenocorticotropic hormone (ACTH) in response to administration of currently available ovine corticotropin-releasing hormone (oCRH) preparations, a complete evaluation of the hypothalamic-pituitary-adrenal axis in cats has not been possible.
This study was undertaken to (1) determine the pituitary (ACTH) and adrenal (cortisol) response to both IV and IM administration of a currently available oCRH product in healthy cats, and (2) validate an endogenous ACTH assay for use in cats.
Seventeen healthy cats receiving oCRH (n = 11) or placebo (n = 6).
Prospective, randomized, placebo-controlled study. oCRH at 1 μg/kg or placebo was given either IM or IV. Endogenous cortisol and ACTH concentrations were evaluated after the injection. A comparison of IM versus IV and placebo versus treatment was made.
The DiaSorin immunoradiometric assay (IRMA) assay for ACTH performed well, showing both parallelism and acceptable intra- and interassay coefficients of variation. There was a significant difference between groups (P = .025) and a significant difference between times (P = .025) when endogenous ACTH concentrations were compared after oCRH IV or IM. No significant differences were observed in cortisol concentrations comparing IV to IM oCRH.
IM administration of oCRH results in significantly greater ACTH concentrations but not cortisol concentrations when compared with IV administration. Samples should be drawn before and at 60 minutes after the injection. The Diasorin IRMA is valid for feline endogenous ACTH measurements.