[The role of group-A10 dopamine neurons of the ventral tegmental area in analgesia evoked by electrocutaneous pain stimulation and morphine].

The activity of antinociceptive mechanisms induced by footshock (FS) and morphine injection was studied in experiments on rats with bilateral destruction of group A10 neurones of the ventral tegmental area. The latent periods of the hot plate and tail flick pain reactions to FS and morphine increased significantly in the experimental and control groups as compared to the initial values. In morphine injection these indices were the same in the experimental and control groups.

[Effect of amitriptyline on analgesia induced by acupuncture and inescapable painful electrodermal stimulation in the rat].

The effect of amitriptyline (1.5 and 3 mg/kg intraperitoneally once a day for 1, 3, 5 days) on the latencies (L) of hot plate (HP) and tail flick (TF) at rest, after acupuncture (A) of bilateral Ho-ku and after inescapable foot-shock (IFS--1.0 mA, 50 Hz, 5 min) was studied in experiments on rats.

[The role of catecholaminergic group-A5 neurons in analgesia induced by auricular electroacupuncture and in electrodermal pain stimulation].

The activity of antinociceptive mechanisms of auricular electroacupuncture (AEA) and footshock (FS) was studied on rats with bilaterally lesioned group A5 neurones. It was shown that the activity of the antinociceptive mechanisms triggered in experimental rats as compared to control rats. The data reveal the involvement of A5-nuclei in the antinociceptive mechanisms of AEA and FS.

[The role of group A5 catecholaminergic neurons in stress and morphine analgesia mechanisms in rats].

The activity of antinociceptive mechanisms in cold stress and under the effect of morphine was studied in experiments on rats subjected to bilateral destruction of group A5 neurons. In cold stress in rats of the experimental and control groups the latent periods (LP) of pain reactions of limb licking differed significantly, both in initial values and between the groups; in contrast, the LP of the tail-flick reaction did not differ significantly. Under the effect of morphine the pain reactions increased authentically as compared to the initial values both in the experimental and the control groups, but there were no significant differences between the groups.

[The selective role of the nucleus raphe magnus in the mechanisms of analgesia in electrocutaneous pain stimulation, cold stress and the action of morphine].

Inhibition of the analgetic activity of systemic morphine and inescapable foot shock in certain moments of the experiment was shown on rats subjected to electrolytic destruction of nucleus raphe magnus. Cold swim stress increased analgesia as compared to the control animals. It is concluded that this formation of the brain is selectively and dynamically involved in mechanisms of various types of analgesia.