Activation of presynaptic alpha-noradrenaline receptors in rat brain by the potent dopamine-mimetic N,N-dipropyl-5,6-ADTN.
Rat cerebral cortex slices labeled with 3H-noradrenaline (NA) were superfused and 3H-NA release was induced with 20 mM K+. The release of 3H-NA was not affected by DA (1 micro M), but was inhibited by the 2-aminotetralins, 5,6-ADTN and N,N-dipropyl-5,6-ADTN (at a concentration of 1 micro M) by about 27% and 65%, respectively. The inhibitory effect of N,N-dipropyl-5,6-ADTN was concentration-dependent (3 x 10(-8) to 3 x 10(-7) M) and was antagonized by phentolamine but not by fluphenazine. The data indicate that, in addition to activating dopamine receptors, N,N-dipropyl-5,6-ADTN stimulates presynaptic alpha-NA receptors.
D000818:Animals; D001921:Brain / Q000187:drug effects*; D004298:Dopamine / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D009281:Naphthalenes / Q000494:pharmacology*; D009638:Norepinephrine / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D009281:Naphthalenes; D011941:Receptors, Adrenergic; D011942:Receptors, Adrenergic, alpha; D013764:Tetrahydronaphthalenes; C015842:2-(N,N-dipropyl)amino-5,6-dihydroxytetralin; D011188:Potassium; D004298:Dopamine; D009638:Norepinephrine