The uptake and release of [3-H]-2-amino-6,7-dihydroxy-1,2,3,4-tetrahydronaphthlane (ADTN) by striatal nerve terminals.
A study has been made of the uptake and release of [G-3H]-2-amino 6,7-dihydroxy-1,2,3,4-tetrahydronaphthalene (ADTN) by crude striatal synaptosomes of the rat. 2 Uptake was rapid, temperature-dependent and could be suppressed by a variety of metabolic inhibitors. 3 The Michaelis-Menten kinetincs indicated the presence of two distinct transport systems in the striatum which were of much higher capacity than those found in the cerebellum, which lacks dopaminergic innervation. 4 Uptake of [3-H]ADTN was strongly inhibited by dopamine and the two potent dopamine-uptake inhibitors, benztropine and nomifensine, but only weakly by imipramine and amphetamine (the latter in non-reserpine-treated animals). 5 Accumulated [3-H]ADTN could be released from striatal slices by elevated K+. A similar release was evoked upon the addition of the ionophore, A23187. 6 The most potent releaser of [3-H]ADTN was (+)-amphetamine. This effect occurred at concentrations inactive against ADTN uptake. The neuroleptic cis-flupenthixol produced an inhibition of the spontaneous release. 7 It is concluded that [3-H]ADTN is accumulated preferentially into areas of the rat brain rich in dopamine. The pharmacological specificity of the uptake suggests that it is a good substrate for the dopamine carrier. Following uptake, [3-H]-ADTN may be released by K+ and a calcium ioniphore, which raises the possibility that ADTN might act as a false transmitter.
D000662:Amphetamines / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D003342:Corpus Striatum / Q000378:metabolism; D003986:Dibenzocycloheptenes / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005475:Flupenthixol / Q000494:pharmacology; D007097:Imines / Q000494:pharmacology; D066298:In Vitro Techniques; D009284:Naphthols / Q000378:metabolism* / Q000494:pharmacology; D009627:Nomifensine / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D051381:Rats; D013565:Sympatholytics; D013574:Synaptosomes / Q000378:metabolism*
D000662:Amphetamines; D003986:Dibenzocycloheptenes; D007097:Imines; D009284:Naphthols; D013565:Sympatholytics; D009627:Nomifensine; D005475:Flupenthixol; D011188:Potassium; D002118:Calcium