Autoradiographic mapping of [3H]sumatriptan binding in cat brain stem and spinal cord.
In vitro autoradiography was performed on sections of cat brain stem and spinal cord using [3H]sumatriptan. Localization studies using 20-25 nM [3H]sumatriptan showed specific binding to cells in the trigeminal nucleus caudalis and nucleus tractus solitarius of the brain stem and the dorsal horn of the spinal cord. This binding was unaffected by 8-hydroxy-dipropylaminotetralin (20 nM), but was abolished by 5-carboxamidotryptamine (200 nM). Ketanserin displaced total specific binding in the brain stem with a pIC50 of 6.2 but no apparent regional specificity. These results indicate that [3H]sumatriptan labels predominantly 5-HT1D alpha and/or 5-HT1D beta (but not 5-HT1A or 5-HT1F) receptor subtypes in cat brain stem and spinal cord.
Mills
A
A
Receptor Pharmacology Group, Wellcome Research Laboratories, Beckenham, Kent, UK.
Martin
G R
GR
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D001345:Autoradiography; D001933:Brain Stem / Q000187:drug effects / Q000378:metabolism*; D002415:Cats; D007650:Ketanserin / Q000494:pharmacology; D008297:Male; D011985:Receptors, Serotonin / Q000378:metabolism; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D017552:Solitary Nucleus / Q000187:drug effects / Q000378:metabolism; D013116:Spinal Cord / Q000187:drug effects / Q000378:metabolism*; D018170:Sumatriptan / Q000378:metabolism*; D014278:Trigeminal Nuclei / Q000187:drug effects / Q000378:metabolism
D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D018170:Sumatriptan; D007650:Ketanserin