Genetic and ontogenetic variations in locomotor activity following treatment with scopolamine or d-amphetamine.
Highly inbred mice of 3 strains (A/J, DBA/2J, and C57BL/6J) were tested in an open field at 14, 21, or 28 days of age. Ten minutes prior to testing, mice received treatment of saline, scopolamine (.5 or 1.0 mg/kg of body weight), or d-amphetamine (.5, 1.0, or 5.0 mg/kg). The d-amphetamine (5.0 mg/kg) increased activity in all strains at 14 days and 28 days of age, and at 21 days significantly increased activity in all except the C5BL/6. In contrast, increased activity with the scopolamine treatment was seen in DBA/2 at 21 days, but not in A and C57BL/6 until 28 days postnatally. The data support a caudal-rostral gradient of brain development with the inhibitory cholinergic system developing more slowly than the excitatory catecholamine system. In addition, strain-specific differences in activity levels are discussed in relation to the differential rates of chloinergic maturation.
D000367:Age Factors; D000818:Animals; D003913:Dextroamphetamine / Q000494:pharmacology*; D004298:Dopamine / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D051379:Mice; D008805:Mice, Inbred A; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009043:Motor Activity / Q000187:drug effects*; D009474:Neurons / Q000254:growth & development; D009638:Norepinephrine / Q000378:metabolism; D011950:Receptors, Cholinergic / Q000187:drug effects; D011954:Receptors, Dopamine / Q000187:drug effects; D012601:Scopolamine / Q000494:pharmacology*; D013045:Species Specificity
D011950:Receptors, Cholinergic; D011954:Receptors, Dopamine; D012601:Scopolamine; D003913:Dextroamphetamine; D004298:Dopamine; D009638:Norepinephrine