Serum protein binding of prednisolone in four species

The protein binding of prednisolone in serum from humans, rabbits, dogs, and rats was determined by equilibrium dialysis. Two nonlinear least-squares regression programs were used to characterize transcortin and albumin binding of the steroid. The animal species differed markedly in their ability to bind prednisolone, but the rabbit was most similar to humans in transcortin concentration and affinity constant.