Effects of cholinergic agents on locomotor activity of P and NP rats

S. N. Katner, W. J. McBride, L. Lumeng, T. K. Li, J. M. Murphy

Research output: Contribution to journalArticle

8 Scopus citations


Experiments were undertaken to compare the selectively bred, alcohol- preferring (P) and alcohol-nonpreferring (NP) rat lines for differences in the locomotor activity (LMA) response to intracerebroventricular infusions of muscarinic- and nicotinic-cholinergic agents. Scopolamine, a nonselective muscarinic antagonist (40 to 120 μg/0.5 μl), dose-dependently increased LMA in both P and NP rats (up to 90 to 100% above baseline; p < 0.05). On the other hand, pirenzepine, a selective M1 muscarinic antagonist (10 to 80 μg/0.5 μl), decreased LMA in P and NP rats (as much as 35 to 40% below control values; p < 0.05). Mecamylamine, a nicotinic antagonist (20 to 120 μg/0.5 μl), also decreased LMA in P and NP rats (as much as 30 to 40% below baseline; p < 0.05). The agonist nicotine (20 to 80 μg/0.5 μl) dose- dependently decreased LMA in both P and NP rats (to a maximum of < 60 to 65% below control values; p < 0.05). Based on standardized z-scores, NP rats were more sensitive (p < 0.05) to the locomotor depressant effects of nicotine than P rats, whereas no differences were observed for standardized z-scores between the P and NP lines on the effects of scopolamine, pirenzepine, or mecamylamine on LMA. The results suggest that subtypes of muscarinic and nicotinic receptors are involved in regulating LMA in a complex manner, with the M1 subtype possibly mediating behavioral activation, and that P and NP rats may possess innate differences in CNS nicotinic receptors regulating LMA.

Original languageEnglish (US)
Pages (from-to)1004-1010
Number of pages7
JournalAlcoholism: Clinical and Experimental Research
Issue number6
StatePublished - Jan 1 1996



  • Alcohol-Nonpreferring Rats
  • Alcohol-Preferring Rats
  • Locomotor Activity
  • Muscarinic Antagonists
  • Nicotinic Antagonist

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Toxicology

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