Nicotine blocks ethanol and diazepam impairment of air righting and ethanol impairment of maze performance.
Results of our previous research in rats demonstrate the following: (a) Angiotensin II (Ang II) inhibits long term potentiation (LTP) in dentate granule cell-perforant path synapses and that this inhibition can be blocked by losartan, an Ang II AT1 receptor antagonist; (b) both ethanol and diazepam inhibit LTP induction and this inhibition can be blocked by losartan; (c) impairment of air righting by ethanol and diazepam (DZ) and eight-arm radial maze performance by ethanol can be blocked by pretreatment with losartan: (d) inhibition of dentate granule cell LTP by Ang II can also be prevented by pretreatment with nicotine. Therefore, it seemed reasonable to hypothesize that ethanol and diazepam impairment of air righting and maze performance might also be blocked by pretreatment with nicotine. The purpose of the present study was to determine the effects of nicotine 0.1, 0.2, 0.3, and 0.4 mg/kg subcutaneously (SC) on 2.0 g/kg ethanol per os (PO) and 1.0 and 2.0 mg/kg DZ intraperitoneally (i.p.) induced impairment of air righting; and to determine if the impaired maze performance due to 2.0 g/kg ethanol PO could be prevented by pretreatment with 0.4 mg/kg of nicotine, SC. Results confirm the hypothesis that moderate doses of ethanol, 2.0 g/kg PO, and DZ, 1.0 mg/kg i.p. impair air righting and that the impairment can be prevented by pretreatment with nicotine SC. Nicotine was not effective in blocking the 2.0 mg/kg DZ impairment of air righting. Nicotine, 0.4 mg/kg SC, prevented the impaired maze performance induced by 2.0 g/kg ethanol PO.
Tracy
H A
HA
Division of Life Sciences, The University of Texas at San Antonio, 78249-0662, USA.
Wayner
M J
MJ
Armstrong
D L
DL
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002492:Central Nervous System Depressants / Q000494:pharmacology*; D003975:Diazepam / Q000494:pharmacology*; D000431:Ethanol / Q000494:pharmacology*; D017774:Long-Term Potentiation / Q000187:drug effects; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D009125:Muscle Relaxants, Central / Q000494:pharmacology*; D009538:Nicotine / Q000008:administration & dosage*; D018722:Nicotinic Agonists / Q000008:administration & dosage*; D004856:Postural Balance / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D002492:Central Nervous System Depressants; D009125:Muscle Relaxants, Central; D018722:Nicotinic Agonists; D000431:Ethanol; D009538:Nicotine; D003975:Diazepam