title: Varying expression of opioid receptors and GTP-binding proteins in human pheochromocytomas.
abstract: The expression of opioid receptors and GTP-binding proteins was studied in 14 pheochromocytomas. The amounts of [3H]diprenorphine bound to membranes varied from 13 to 62 fmole/mg protein, but significantly higher in adrenaline-secreting tumors than in noradrenaline-secreting tumors. None of [3H]DADLE, [125I]beta-endorphin or [3H]ethylketocyclazocine binding was correlated with [3H]diprenorphine binding. Gpp(NH)p inhibition of [3H]DADLE binding was evident in all four normal human adrenal medullae but in only 8 out of 14 pheochromocytomas. The extent of Gpp(NH)p inhibition was not correlated with the amount of pertussis toxin (PT)-sensitive GTP-binding proteins as measured by PT-catalyzed [32P]ADP-ribosylation. The present findings suggest that opioid receptors and PT-sensitive GTP-binding proteins are variously expressed in transformed chromaffin cells, pheochromocytoma.
authors.affiliation: Dept. of Med., Gero Hot Spring Hospital, Gifu, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kamikubo
authors.forename: H
authors.initials: H
authors.lastname: Murase
authors.forename: M
authors.initials: M
authors.lastname: Niwa
authors.forename: K
authors.initials: K
authors.lastname: Miura
authors.forename: Y
authors.initials: Y
authors.lastname: Miura
authors.forename: T
authors.initials: T
authors.lastname: Satoh
authors.forename: A
authors.initials: A
authors.lastname: Tomita
authors.forename: S
authors.initials: S
authors.lastname: Nakamura
authors.forename: T
authors.initials: T
authors.lastname: Miyashita
authors.forename: T
authors.initials: T
authors.lastname: Imai
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D003496:Cyclazocine / Q000031:analogs & derivatives / Q000378:metabolism; D004174:Diprenorphine / Q000378:metabolism; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000378:metabolism; D016308:Enkephalin, Leucine-2-Alanine; D016314:Ethylketocyclazocine; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D010673:Pheochromocytoma / Q000378:metabolism*; D011957:Receptors, Opioid / Q000378:metabolism*; D001615:beta-Endorphin / Q000378:metabolism
chemical_list: D011957:Receptors, Opioid; D004174:Diprenorphine; D016314:Ethylketocyclazocine; D004743:Enkephalin, Leucine; D001615:beta-Endorphin; D016308:Enkephalin, Leucine-2-Alanine; D019204:GTP-Binding Proteins; D003496:Cyclazocine