Nociceptive reactions during stimulation of immunity in rats with different individual sensitivities to stress.

Different nociceptive reactions and individual resistance were studied in rats in the initial state and in conditions of stimulation of immune processes by various methods. The aims were to study the effect of the preparation Imunofan, an immune stimulator, on various behavioral manifestations of pain reactions in animals with different individual resistances to stress and to compare the results with similar data in a natural model of immune activation. Detection of the central, immune-dependent component of the regulation of nociceptive reactions was addressed using intracerebroventricular administration of the study compound.

[Nociceptive reactions during stimulation of immunity in rats with various individual resistance to stress].

Various behavioural nociceptive reactions and individual resistance against stress were studied under conditions of stimulation of the immune processes by various techniques. The research problems included a study of influence of the immune stimulation with preparation "Imunofan" upon pain responses depending on individual resistance of animals to a stress, and the obtained results were compared with similar data in natural model of immune activation. To reveal central immune regulation of nociceptive reactions, imunofan was injected into brain ventricles.

[Morphine antibodies in the mechanisms of morphine resistance, morphine tolerance and of the action of an antagonist].

It was found that the absence of the analgesic effect of morphine, as determined by the tail-flick test, in morphine-resistant and morphine-tolerant rats, as well as in naloxane blockade of morphine analgesia in morphine-sensitive rats was attended with a four- to eight-fold increase in morphine antibodies in the plasma, as determined by the ELISA method. It is suggested that a pharmacokinetic factor mediated through immune reactions of morphine antibodies formation is one of the mechanisms of such conditions.