Minor alkaloids of tobacco release [3H]dopamine from superfused rat striatal slices.
In addition to S(-)-nicotine, several minor tobacco alkaloids ((+/-)-nornicotine, anabaseine, S(-)-anabasine, and S(-)-N-methylanabasine) are present in tobacco smoke. This study demonstrates that these alkaloids increase fractional 3H release in a concentration-dependent manner from rat striatal slices preloaded with [3H]dopamine, with desensitization of this response. The rank order of EC50 values was S(-)-nicotine (3.0 +/- 2.2 microM) > (+/-)-nornicotine (6.7 +/- 2.1 microM) > anabaseine (15.4 +/- 6.1 microM) = S(-)-N-methylanabasine (16.3 +/- 4.7 microM) = S(-)-anabasine (19.3 +/- 3.2 microM). The alkaloids did not modulate fractional 3H release evoked by electrical-field depolarization. Thus, minor tobacco alkaloids may contribute to the apparent neuroprotective effects of smoking in neurodegenerative diseases.
Dwoskin
L P
LP
College of Pharmacy, University of Kentucky, Lexington 40536, USA.
Teng
L
L
Buxton
S T
ST
Ravard
A
A
Deo
N
N
Crooks
P A
PA
D000691:Anabasine / Q000031:analogs & derivatives* / Q000494:pharmacology*; D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D008297:Male; D009538:Nicotine / Q000031:analogs & derivatives* / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
D009538:Nicotine; C005311:nornicotine; C091713:anabaseine; D000691:Anabasine; D004298:Dopamine