Opposite effects of N,N-dimethyltryptamine (DMT) and 5-methoxy-n,n-dimethyltryptamine (5-MeODMT) on acoustic startle: spinal vs brain sites of action.
Neuroscience and biobehavioral reviews January 1, 1982 R L Commissaris, M Davis 25 citations
The hallucinogens DMT and 5-MeODMT have opposite effects on the acoustic startle response in rats when given systemically: DMT depresses it while 5-MeODMT increases it. When injected directly into the brain, both drugs depress startle equally. When injected into the spinal cord, 5-MeODMT increases startle but DMT has no effect. Tests using electrical stimulation of a brainstem nucleus confirm that 5-MeODMT acts in the spinal cord to enhance startle, whereas DMT does not. The authors suggest that the differing behavioral effects of these drugs may depend on whether their action is primarily in the brain (where both are equally potent) or the spinal cord (where only 5-MeODMT is active).