Okumura K, Ujike H, Akiyama K, Kuroda S
Department of Neuropsychiatry, Okayama University Medical School, Japan.
J Neural Transm (Vienna). 1996;103(10):1153-61. doi: 10.1007/BF01271200.
To clarify clinical roles of sigma receptor binding affinity of neuroleptics, neck dystonia induced by microinjection of sigma receptor ligands and neuroleptics into rat red nucleus was investigated. DTG and (+)-3-PPP, putative sigma receptor agonists, induced neck dystonia in dose-dependent and reversible manner. Haloperidol and perphenazine induced dystonia in the same way as sigma receptor agonists, whereas zotepine and (-)-sulpiride did not. The rank order of potency in induction of dystonia and sigma receptor affinity of these compounds showed positive correlation. Although BMY-14802 has a high affinity for sigma receptors, it never produced dystonia by itself. On the other hand, combined injection of BMY-14802 with DTG attenuated DTG-induced dystonia. Therefore, it is suggested that typical neuroleptics such as haloperidol act agonistic and atypical neuroleptics such as BMY-14802 act antagonistic at rubral sigma receptors in the induction of neck dystonia.
