Investigation of enhancement effects of nicotine on cholinergic neurotransmission in isolated rabbit gastric fundus: role of antioxidants.
Nicotine, which is tobacco alkaloid, still induces interests for researchers because of smokers addiction to nicotine. Nicotine having influence on the neuronal acetylcholine receptors (nAChRs) increases release of most certain neurotransmitters from the nerve endings. Also, nicotine, affecting the mitochondrial respiratory chains, contributes to the formation of reactive oxygen species. In the present study, we investigated the effects of nicotine on smooth muscles of gastric fundus on the electrical field stimulation (EFS) that induces transition contraction via stimulation nAChRs. In addition, we aimed to investigate the interaction between release of acetylcholine, induced by nicotine, and the effects of reactive oxygen species. Therefore, the effects of allopurinol (10(-6)-10(-5) M), deferoxamine (10(-4) M) and mannitol (10(-4)-5 x 10(-3) M) were tested on the transient contraction induced by nicotine. In conclusion, mannitol (5 x 10(-3) M) significantly reduced contractile response to nicotine on EFS only in high concentration. Whereas in small concentrations mannitol (10(-4) M) statistically did not cause any results. Deferoxamine and allopurinol also did not have any significant response.
Anuvarbekova
A
A
Department of Pharmacology, Medical School, Gazi University, 06510 Besevler, Ankara, Turkey.
Fincan
G S O
GS
Vural
I M
IM
Ozger
S I
SI
Ercan
Z S
ZS
Utkan
T
T
Sarioglu
Y
Y
D000109:Acetylcholine / Q000378:metabolism; D000493:Allopurinol / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001285:Atropine / Q000494:pharmacology; D002799:Cholinergic Fibers / Q000187:drug effects*; D003676:Deferoxamine / Q000494:pharmacology; D004558:Electric Stimulation; D005748:Gastric Fundus / Q000187:drug effects*; D066298:In Vitro Techniques; D008353:Mannitol / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009388:Neostigmine / Q000494:pharmacology; D009538:Nicotine / Q000494:pharmacology*; D011817:Rabbits; D017382:Reactive Oxygen Species / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects*; D013779:Tetrodotoxin / Q000494:pharmacology
D000975:Antioxidants; D017382:Reactive Oxygen Species; D009388:Neostigmine; D008353:Mannitol; D013779:Tetrodotoxin; D000493:Allopurinol; D009538:Nicotine; D001285:Atropine; D003676:Deferoxamine; D000109:Acetylcholine