[Relationship between cortisol metabolic clearance rate and cortisol concentrations in adult male dexamethasone treated guinea-pigs (author's transl)].

Continuous infusion of increasing unlabelled cortisol concentrations and tritiated cortisol was used to state precisely the relation between metabolic clearance rate of cortisol (MCR) and blood cortisol levels, on conscious male adult guinea-pigs under chronic cannulation and treated by dexamethasone. The MCR of cortisol depends on blood cortisol levels : constant for low values of cortisol concentrations (5 and 20 micrograms/100 ml), it rises 50 % between 20 and 50 micrograms/100 ml : from cortisol levels of 50 to 300 micrograms/100 ml, it reaches a maximala and constant value.