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V V Mikheev

Publications and source records attributed to V V Mikheev.

32 records · Page 2Linked to original sources
PubMedDate not supplied

[Effect of morphine and naloxone on the biorhythm of pain sensitivity of mice after unilateral inactivation of cerebral hemispheres].

The effects of morphine (5 mg/kg, i.p.) and naloxone (1 mg/kg, i.p.) on the formation of pain sensitivity biorhythms was studied in the tail-flick test on adult male SHR mice upon unilateral inactivation of cerebral hemispheres by Leao's method of spreading potassium depression. It was established that morphine changed the rhythmogenic properties of both left and right hemispheres, inverted the phase of circadian rhythm, and produced the most pronounced analgesic action in the stage of maximum pain sensitivity (minimum pain threshold). Naloxone affected the pain rhythm predominantly in the operated and right-hemisphere-active animals, which confirmed the increased role of opioids in the process of rhythm regulation in mice.

Analgesics, Opioid↗
PubMedDate not supplied

[Hemispheric participation in the shaping of spatial-motor asymmetry in visual recognition in rats].

Asymmetry of movement direction was found in Wistar rats at establishing of motor alimentary conditioned reflex to simultaneously presented visual stimuli. In the course of learning the asymmetry weakened on the whole, but some individuals retained right- or left side preference. The analysis of asymmetry change before and after unilateral cortical inactivation revealed a special role of right hemisphere influences for the formation of right-side preference and of the left hemisphere--for the choice of the left direction. The lack of asymmetry was observed at the presence of the influences from the left hemisphere cortex depressing ipsilateral nigro-striate system and activating the contralateral one. Influences of the cortex of both hemispheres reduce the absolute value of the asymmetry coefficient; the left hemisphere has a special significance for manifestation of temporal asymmetry parameters. Photic interference is a factor modulating the asymmetry. It reduces the right hemisphere activity more than that of the left one; it intensifies right hemisphere influences, contributes to the involvement of the transcallosal conduction channel in the formation of spatial-motor asymmetry.

Animals↗
PubMedDate not supplied

[Effect of unilateral spreading cortical depression on intraspecies aggression and sociability of isolated mice].

It has been shown that aggressive forms of behaviour are controlled preferentially by the left hemisphere and sociability by the right one. Consequently, the opposite poles of the continuum "aggression-sociability" have different lateralization. Interconnection between functional interhemispheric asymmetry and aggression degree has been revealed: in high-aggressive mice the differences in the effect of left and right hemispheres inactivation are expressed stronger as compared to low-aggressive and nonaggressive animals.

Aggression↗
PubMedDate not supplied

[Resistance of visual recognition to interference in the intact and callosotomized rat].

Recognition of structured visual stimuli under the action of light interference was studied by means of conditioning in rats with intact and dissected callosal body. Addition of noise to conditioned signals was achieved by insertion of additional element into their image. It was found that as more noise was added the number of correct responses decreased and latencies of conditioned food-procuring reactions became longer. The number of individuals in the sample, which possessed a differentiation level higher than the random one decreased. Noise immunity of males in the range of weak and average noises proved to be higher than in females, and, as a rule, equal at high noises. Section of the callosal body produced changes in noise immunity of visual recognition; the nature and degree of the changes depended on the intensity of noise and on the animal's sex. The existence of modulating callosal influences on noise immunity of visual recognition is suggested.

Animals↗