Acute and chronic effects of methylphenidate on cortical adrenoceptors in the rat.
The effects of acute and chronic treatments with methylphenidate were examined on cortical adrenoceptors. A single dose of methylphenidate increased the affinity of [3H]prazosin and [3H]idazoxan binding sites. Acute and chronic methylphenidate treatments caused a down-regulation of alpha 1-adrenoceptors. There were no changes in cortical beta-adrenoceptors measured with [3H]dihydroalprenolol nor in endogenous monoamine levels. The alterations in alpha-adrenoceptors can be attributed to an indirect action of methylphenidate possibly through an accrued release of noradrenaline or tyramine.
Mathieu
J F
JF
Département de Physiologie, Faculté de Médecine, Université de Montreal, Québec, Canada.
Ferron
A
A
Dewar
K M
KM
Reader
T A
TA
D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism; D002395:Catecholamines / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008774:Methylphenidate / Q000494:pharmacology*; D011224:Prazosin / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011941:Receptors, Adrenergic / Q000187:drug effects*
D015306:Biogenic Monoamines; D002395:Catecholamines; D011941:Receptors, Adrenergic; D008774:Methylphenidate; D011224:Prazosin