The N-methyl-D-aspartate receptor channel complex and the sigma site have different target sizes.
Radiation inactivation technique has been used to measure the molecular sizes of the N-methyl-D-aspartate (NMDA) receptor and the sigma recognition site. Target size analysis of [3H]MK-801 (dizocilpine maleate) binding to the NMDA receptor channel complex in rat cortical membranes has given a molecular size of 128,000 +/- 9,000 Da. This is in contrast to the target size of the sigma site in the same tissue as labelled by [3H]DTG (ditolylguanidine), giving a value of 36,000 +/- 2,900 Da. These studies have provided evidence for a clear difference in the molecular sizes of these two recognition sites.
Wong
E H
EH
Merck, Sharp and Dohme Research Laboratories, Neuroscience Research Centre, Harlow, U.K.
Nielsen
M
M
D000818:Animals; D001923:Brain Chemistry; D002540:Cerebral Cortex / Q000378:metabolism; D003986:Dibenzocycloheptenes / Q000378:metabolism; D016291:Dizocilpine Maleate; D006146:Guanidines / Q000378:metabolism; D066298:In Vitro Techniques; D007473:Ion Channels / Q000378:metabolism*; D008566:Membranes / Q000187:drug effects / Q000378:metabolism; D008970:Molecular Weight; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter / Q000378:metabolism*; D011957:Receptors, Opioid / Q000378:metabolism*; D017465:Receptors, Opioid, delta
D003986:Dibenzocycloheptenes; D006146:Guanidines; D007473:Ion Channels; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D016291:Dizocilpine Maleate; C050232:1,3-ditolylguanidine