An examination of the opiate receptor subtypes labeled by [3H]cycloFOXY: an opiate antagonist suitable for positron emission tomography.
17-Cyclopropylmethyl-3,14-dihydroxy-4,5-alpha-epoxy-6-beta-fluoromorp hinan (cycloFOXY) is a fluorinated derivative of naltrexone suitable for labeling opiate receptors using positron emission transaxial tomography. Using the quantitative ligand binding method "binding surface analysis," in vitro autoradiography, and site-directed alkylating agents, [3H]cycloFOXY is shown to label mu and kappa opiate binding sites in vitro. Similar results were obtained using [3H]naloxone. Additional experiments demonstrate that [3H]cycloFOXY administered in vivo also labels mu and kappa binding sites. The relevance of these findings are discussed from clinical and basic science perspectives.
D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000378:metabolism*; D004399:Dynorphins / Q000378:metabolism; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004745:Enkephalins / Q000378:metabolism; D008297:Male; D009270:Naloxone / Q000378:metabolism; D009271:Naltrexone / Q000031:analogs & derivatives* / Q000378:metabolism; D010446:Peptide Fragments / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000378:metabolism*; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; D013570:Synaptic Membranes / Q000378:metabolism; D014055:Tomography, Emission-Computed
D004745:Enkephalins; D010446:Peptide Fragments; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa; D017450:Receptors, Opioid, mu; C034565:naloxone receptor; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D009270:Naloxone; D009271:Naltrexone; D004399:Dynorphins; C026770:dynorphin (1-8); C043394:3-acetyl-6-deoxy-6-fluoronaltrexone