Observation on the Plasma Cortisol (Hydrocortisone) of Normal Dogs by Radioimmunoassay Method

The plasma cortisol concentrations in 60 normal dogs were determined by radioimmunoassay.According to the plasma cortisol values the dogs might be divided into 3 types,I.e.8:00 AM-low concentration with 5:00 PM-high concentration is called type A (30 dogs),8:00 AM-high concentration with 5:00 PM-low concentratiin is called type B (20 dogs),while 8:00 through 5:00 PM proximal concentration is called type C (10 dogs).We found that the circadian rhythms of the bio-o clock of plasma cortisol secretion in type B dogs were appeared in "U-form".There were two kinds of causation in these 3 type dogs:1)The plasma cortisol secretion of dogs were closely depended on the species of dogs.2)The plasma cortisol secretion of dogs were related with their envirements and their variant "lifeatyle".