Nicotine produces antidepressant-like actions: Behavioral and neurochemical evidence.
Converging lines of evidence indicate the involvement of nicotinic acetylcholine receptors in depressive illness and antidepressant drug action. We investigated the effects of sub-chronic and chronic treatment with imipramine, nicotine and their combination on: (a) the ability of a dopamine-mimetic challenge to produce locomotor stimulation and (b) cortical density of beta-adrenoceptors. One week of treatment with imipramine (10 mg/kg, twice daily) did not result in an altered response to the apomorphine (0.15 mg/kg) challenge, but after 2 weeks, the imipramine-treated rats demonstrated hyperactivity. Conversely, such increased locomotor response was observed in rats treated with nicotine (0.4 mg/kg, twice daily) for 1 but not for 2 weeks. Groups treated with nicotine+imipramine for 1 and 2 weeks demonstrated equally high hyperactivity in response to the apomorphine challenge. This effect was not different from the effects of 1-week treatment with nicotine or 2-week treatment with imipramine. The density of beta-adrenoceptors was equally decreased by 2 (but not 1) weeks of the treatment with imipramine, nicotine and their combination. The present behavioral and neurochemical data suggest the antidepressant-like effect of the chronic treatment with nicotine. It appears that the potentiation of the dopamine-mimetic-induced hyperactivity cannot be explained by beta-adrenoceptor down-regulation.
Popik
Piotr
P
Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna Street, 31-343 Kraków, Poland. nfpopik@cyf-kr.edu.pl
Krawczyk
Martyna
M
Kos
Tomasz
T
Nalepa
Irena
I
Kowalska
Marta
M
Witarski
Tadeusz
T
Antkiewicz-Michaluk
Lucyna
L
Vetulani
Jerzy
J
D018759:Adrenergic Uptake Inhibitors / Q000494:pharmacology; D000704:Analysis of Variance; D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D001058:Apomorphine / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects*; D002540:Cerebral Cortex / Q000737:chemistry / Q000187:drug effects; D018491:Dopamine Agonists / Q000494:pharmacology; D007099:Imipramine / Q000494:pharmacology; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009538:Nicotine / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000378:metabolism; D013997:Time Factors
D018759:Adrenergic Uptake Inhibitors; D000928:Antidepressive Agents; D018491:Dopamine Agonists; D011943:Receptors, Adrenergic, beta; D009538:Nicotine; D001058:Apomorphine; D007099:Imipramine