Pharmacokinetics of antipyrine, paracetamol, and morphine in rat at 71 ATA

The pharmacokinetics of [14C]antipyrine, [3H]paracetamol, and [3H]morphine were studied in male Wistar rats at 1 ATA and then at 71 ATA, each animal being its own control. Separate control groups were studied at 1 ATA in order to test the validity of the one-way crossover protocol. The drugs were injected through a femoral venous catheter, and blood was sampled from a catheter in the femoral artery. There were no significant differences in the biological half-life (T1/2), the apparent volume of distribution (Vd), and the clearance (C) of antipyrine and paracetamol. Likewise, there was no appreciable effect of high pressure on the blood concentration profile of morphine.