The antinociceptive effects of subcutaneous 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) and 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and the responses to intrathecal (i.th.) serotonin (5-HT) and substance P (SP) were examined in mice after repeated administration of 5-MeODMT (3 mg/kg every 30 min for 4 hours). Ninety min after the last injection of 5-MeODMT the basal tail-flick and...
The effect of intrathecal (i.th.) substance P (SP) on antinociception elicited by the serotonin (5-HT) receptor agonist 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) was investigated in mice by means of the tail-flick method. Substance P (0.07, 0.7 or 7 micrograms) induced a behavioral syndrome for 1-2 min, but had no apparent toxic or neurologic effects and did not alter the tail-flick response...