Rapid development of brain beta-adrenoceptor down-regulation induced by phenelzine: subcellular studies.
The distribution of the specific binding of [3H]dihydroalprenolol in sucrose gradients containing homogenates of rat cerebral cortex centrifuged to equilibrium was examined after acute treatment with phenelzine (50 mg/kg i.p.). There was a time-dependent decrease in the number of beta-adrenoceptors in the plasma membrane fractions (0.8-1.0 M sucrose), without any significant alteration in the light density fractions (0.4-0.5 M sucrose). These results suggest that agonist-induced beta-adrenoceptor down-regulation is promoted by a process other than receptor internalization.
Koshikawa
N
N
Department of Pharmacology, Nihon University School of Dentistry, Tokyo, Japan.
Maruyama
Y
Y
Kobayashi
M
M
Campbell
I C
IC
D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects*; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D004082:Dihydroalprenolol / Q000494:pharmacology; D015536:Down-Regulation / Q000187:drug effects*; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D010624:Phenelzine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000378:metabolism*; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism
D011943:Receptors, Adrenergic, beta; D004082:Dihydroalprenolol; D010624:Phenelzine