Structural, functional, and biochemical changes in the brain during modeling of dopamine system disturbances in rats.
Dysfunction of the dopamine system was modeled in Wistar rats by injection of 50 mg/kg L-dopa over 4 weeks. Experimental rats demonstrated considerably decreased locomotor activity and increased emotional strain compared to the control group. Structural changes consisted in a significant decrease in the size of neuronal bodies in the sensorimotor cortex (layers III and V) and caudate nucleus together with changed variability of these parameters compared to the corresponding values in the control. The neuroglial index increased by 22% in layer V, tended to decrease in layer III, and remained unchanged in the caudate nucleus. L-Dopa changed specific activity of enzymes: tyrosine hydroxylase activity in the sensorimotor cortex decreased by 25%, while monoamine oxidase B activity in the caudate nucleus increased by 33%. Thus, dysfunction of the dopamine system resulting in changes in dopamine metabolism not only leads to structural and functional rearrangements reducing functional capacities of the cell systems, but is also associated with compensatory and repair reactions in the brain.
Khudoerkov
R M
RM
Institute of Brain Research, Russian Academy of Medical Sciences, Moscow. rolfbrain@yandex.ru
Dovedova
E L
EL
Voronkov
D N
DN
D000818:Animals; D001921:Brain / Q000166:cytology / Q000187:drug effects / Q000503:physiopathology*; D001923:Brain Chemistry; D004195:Disease Models, Animal; D004298:Dopamine / Q000502:physiology*; D004644:Emotions / Q000187:drug effects; D007980:Levodopa / Q000494:pharmacology; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism; D009043:Motor Activity / Q000187:drug effects; D009457:Neuroglia / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D007980:Levodopa; D014446:Tyrosine 3-Monooxygenase; D008995:Monoamine Oxidase; D004298:Dopamine