| SHORT COMMUNICATION
|Year : 1982 | Volume
| Issue : 2 | Page : 217-222
Effect of restraint stress on morphine antinociception in rats
SK Bhattacharya, D Bhattacharya
The effect of restraint stress (1, 2 and 4 h ) was investigated, in rats, on the antinociceptive action of a sub-analgesic dose (2.0 mg/kg, ip) of morphine. Restraint stress prduced a time-related potentiation of morphine antinociception. Stress (4 h)-induced potentiation of morphine analgesia was significantly attenuated after pretreatment with pharmacological agents known to decrease serotonergic and prostaglandin activity, but not by metyrapone, an inhibitor of endogenous corticoid synthesis.
The results suggest that serotonin and prostaglandins are involved in restraint stress-morphine interaction.The results have been discussed in the context of earlier investigations, reported from this laboratory, indicating increase in rat brain serotonin and prostaglandin activity, following restraint stress. It has been suggested that restraint stress initially activates the proposed, first mediator, prostaglandins, which in turn modulates central serotonergic activity, to induce the observed potentiation of morphine analgesia by restraint stress.
S K Bhattacharya