Cortisol metabolism in the sheep (Romney breed) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science

Thumbnail Image
Open Access Location
Journal Title
Journal ISSN
Volume Title
Massey University
The Author
The metabolism of Cortisol in the normal Romney ewe was investigated by analysis of the radioactive metabolites excreted in the urine following intravenous (I.V.) administration of 4-c14 cortisol. The metabolite glucuronic!os were hydrolysed with b-glucuronidase and extracted from the aqueous medium with ethyl acetate. The neutral fraction was divided into c-19 and c-21 metabolites by sequential elution from a florisil column. Extensive use was made of T.L.C. for the separation and analysis of each fraction before the quantitation of individual components. A series of experiments was performed with, surgically modified sheep involving collection of bile and urine both after I.V. injection of 4-c14 cortisol, and after intraduodenal infusion of radioactive biliary metabolites obtained from I.V. administration of 4-c14 corticol. The metabolites collected at each stage were analysed both qualitatively and quantitatively. The urine collected each hour for 18 consecutive days from a normal sheep, was subjected to colorimetric determination for a-ketol and 17-ketogenic steroid content. The data obtained was analysed for diurnal variation in chromogen output, and the daily secretion rate of cortisol was estimated.
Romney sheep, Romney Marsh sheep, Cortisol