Mr Edd Knowles (PhD student) has been awarded a Petplan Charitable Trust to work on "Equine Pituitary Pars intermedia dysfunction: improving understanding of diagnostic testing".
Pituitary pars intermedia dysfunction (PPID) is a common condition of older horses in which excessive quantities of several hormones are produced by the pituitary gland. The condition can have a wide range of effects and has been associated with an increased risk of laminitis, a potentially catastrophic disease of the equine hoof.
The condition is usually diagnosed by measuring the amount of one of the pituitary hormones (ACTH) in the blood. High concentrations of ACTH indicate PPID although they can occur for other reasons. A human ACTH test is commonly used to make a diagnosis of equine PPID. Our data from an earlier study suggests that other hormones produced by the pituitary in ponies may interfere with the diagnostic test and that the concentrations of these interfering hormones change with the seasons.
Our new grant is to look at the ACTH test in more detail. To understand which other pituitary hormones can interfere with the test and to what extent this could affect test interpretation. Ultimately we hope to understand the reasons for the seasonal changes in these other hormones and their effects. We are collaborating with Dr Cali Hyde and Mr Nigel Stokes at the London Bioanalysis Centre to use mass spectrometry to identify these hormones in equine plasma.