Ontogeny of the electrophysiological activity of dopaminergic cells with special reference to the influence of adrenal medullary grafts on aging.
A variety of neurological impairments during aging involves pathological changes in the basal ganglia, with the consequent deterioration of motor activities. The purpose of this study was to determine whether the extracellular activity of dopaminergic cells of the substantia nigra pars compacta of Wistar rats changes with age, and if so whether ventricular adrenal medullary grafts can influence the electrophysiological activity of the oldest age group. The results indicate that there is a significant decrease in the firing frequency of substantia nigra cells which begins at 18 months of age and is most prominent by 22-24 months of age. The rate of firing was improved with adrenal medulla grafts placed in the lateral ventricle. In addition, it was also observed that with age there is an increase in the number of cells which fire at slower frequencies. Quinpirole administration induced a significant decrease in firing frequency in all age groups, including the grafted animals. These results suggest that in the aged Wistar rats there is an impairment in the response of SNC cells, which can be partially restored by fetal adrenal medullary grafts.
Lavín
M A
MA
Departamento de Neurociencias, Universidad Nacional Autónoma de México, México, D.F.
Drucker-Colín
R
R
D000200:Action Potentials / Q000187:drug effects; D000313:Adrenal Medulla / Q000502:physiology / Q000637:transplantation*; D000375:Aging; D000818:Animals; D002552:Cerebral Ventricles / Q000254:growth & development; D004298:Dopamine / Q000502:physiology*; D004594:Electrophysiology / Q000379:methods; D004873:Ergolines / Q000494:pharmacology; D016332:Fetal Tissue Transplantation / Q000502:physiology; D008297:Male; D019257:Quinpirole; D051381:Rats; D011919:Rats, Inbred Strains; D013378:Substantia Nigra / Q000033:anatomy & histology / Q000187:drug effects / Q000254:growth & development*; D016042:Transplantation, Heterotopic
D004873:Ergolines; D019257:Quinpirole; D004298:Dopamine