[Interaction of various types of opiate receptors of cortical neurons in the turtle during activation by specific agonists].

The influence of polycomponent solutions of agonists of opiate mu-, delta, chi- and sigma-receptors (morphine, D-Ala2, D- Ley5 -enkephalin, bremazocine, SKF 10,047) and of met-enkephalin on the habituation of orthodromic evoked potential in the visual cortical area was studied in turtles. Interaction between the different types of opiate receptors was observed at their combined activation. The interaction resulted in an enhancement or attenuation of modulation of separate phases of evoked potential habituation which differed from simple sum of effects during isolated activation of each type of receptors.