Possible neural mechanisms involved in footshock stress-induced enhancement of exploratory behavior in mice.
The effect of inescapable footshock stress on open-field activity, as measured by the number of ambulations, was studied in male mice. Ambulations significantly increased after footshock stress, the most significant effect appeared after 20 min-stimulation and the effect decreased as footshock time lengthened. The footshock stress-induced enhancement of ambulation was inhibited by haloperidol (0.2, 0.5 and 1 mg/kg), phentolamine (5 and 10 mg/kg), mianserin (20 mg/kg), atropine (0.5, 1 and 2 mg/kg), naltrexone (10 mg/kg) and MK-801 (0.05, 0.1 and 0.2 mg/kg), but was not influenced by propranolol (5, 10 and 20 mg/kg) or diazepam (1, 2 and 5 mg/kg). Haloperidol (0.5 and 1 mg/kg) and mianserin (5, 10 and 20 mg/kg) also exerted an inhibitory effect on non-stressed normal mice. These results suggest that dopaminergic, alpha-adrenergic, cholinergic, opioidergic and N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission systems are involved in the footshock stress-induced ambulatory activation.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002490:Central Nervous System / Q000187:drug effects / Q000502:physiology*; D003975:Diazepam / Q000494:pharmacology; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004558:Electric Stimulation; D005106:Exploratory Behavior / Q000502:physiology*; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D008803:Mianserin / Q000494:pharmacology; D051379:Mice; D009271:Naltrexone / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D013312:Stress, Physiological