title: Daily spontaneous running alters behavioral and neurochemical indexes of nigrostriatal function.
abstract: Behavioral and neurochemical indexes of nigrostriatal dopaminergic function were compared between sedentary control rats (n = 12) and daily spontaneous running (DSR) male rats (n = 10). Nine weeks of DSR did not significantly alter body, heart, pituitary, or testes weights. DSR and control animals did differ in performance on a sensorimotor beam walking task, with DSR rats showing significantly shorter times required to cross the beam (60 +/- 17 vs. 119 +/- 14s; P < 0.02) as well as fewer slips off the beam (3.0 +/- 0.8 vs 6.2 +/- 1.1; P < 0.05). DSR animals also engaged in significantly greater durations of social investigation than control rats (43 +/- 5 vs 25 +/- 3 s; P < 0.01) when tested in a social investigation memory-recognition test. Basal dopamine release rates from superfused corpus striatal tissue fragments of DSR rats were about one-half those obtained from control animals (18 +/- 5 vs. 34 +/- 6 pg.mg-1.min-1; P < 0.05), whereas responses of these striatal tissue fragments to a depolarizing concentration of potassium were virtually identical (45 +/- 10 vs. 47 +/- 8 pg.mg-1.min-1). These data indicate that a relatively limited intensity of DSR insufficient to alter cardiovascular function can exert substantial effects on behavioral and neurochemical indicators of nigrostriatal dopaminergic activity.
authors.affiliation: Department of Anatomy, Northeastern Ohio Universities, College of Medicine, Rootstown 44272-0095, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Dluzen
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.forename: C Y
authors.initials: CY
authors.lastname: Chen
authors.forename: S E
authors.initials: SE
authors.lastname: DiCarlo
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D002851:Chromatography, High Pressure Liquid; D002940:Circadian Rhythm; D003342:Corpus Striatum / Q000166:cytology / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009483:Neuropsychological Tests; D009929:Organ Size; D010477:Perfusion; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011188:Potassium / Q000378:metabolism*; D011597:Psychomotor Performance / Q000502:physiology*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D011188:Potassium; D004298:Dopamine