[Pharmacodynamics of the interaction of neuroleptanalgetics].

The authors carried out a quantitative assessment of pharmacodynamic effects of droperidol (5 and 25 mg/kg) and phentanyl (0.5 and 1 microgram/kg). The effects of the drugs on sensitivity and pain were studied by the "tail jerking" test. The electrophysiological studies included spectral analysis of the EG of the following central nervous system structures: head of the caudate nucleus, substantia nigra, central gray of the midbrain. The quantitative characteristics of the analgesic effect of phentanyl and hyperalgetic effect of droperidol, as well as the potentiation of the antinociceptive effect of phentanyl combined with droperidol were demonstrated. Studies on the EG recorded the appearance of local extremes on the spectrograms within the range of 7 Hz. The use of the method of least squares for comparing the curves of the relationships between the effects of droperidol and phentanyl and their concentrations in the brain enabled deriving the equations that quantitatively characterize the pharmacodynamic effects of interaction of the drugs in question.