Dihydroergotamine binding to rat brain membranes.

³H-dihydroergotamine, which is used clinically to treat orthostatic hypotension and migraine, binds saturably, reversibly and with high affinity (K_D = 0.2 nM) to rat brain membranes. The binding is time, temperature and pH dependent and is highest in the hippocampus and the corpus striatum. Serotonin was the only neurotransmitter tested capable of inhibiting ³H-DHE binding.