Co-alteration of dopamine D2 receptor and muscarinic acetylcholine receptor binding in rat striatum after circling training.
CIRCLING training (CT) decreases muscarinic acetyl-choline receptor (mAchR) binding in rat striatum. As cholinergic and dopaminergic systems interact strongly we evaluated the expression of D2-subtype dopamine receptor (DA D2) and mAchR together after CT. Animals trained from 30 to 37 days of age and sacrificed 2 months later showed an enduring drop in Bmax of 40% in DA D2 and 34% in mAchR. Plotting the percentage of binding drop of both receptors for each animal showed that the reduction of one system correlates with the other (r2 = 0.71, p < 0.01; n = 8). Neither mAchR nor DA D2 were affected when training started at 20 or 60 days. We conclude that the presence of a period where CT exerts long term alterations during development involves both cholinergic and dopaminergic systems.
Ibarra
G R
GR
Laboratorio de Biologia Celular, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
Paratcha
G C
GC
Wolansky
M J
MJ
Azcurra
J M
JM
D000818:Animals; D001667:Binding, Competitive / Q000187:drug effects*; D003342:Corpus Striatum / Q000378:metabolism*; D008297:Male; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017448:Receptors, Dopamine D2 / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000502:physiology*
D017448:Receptors, Dopamine D2; D011976:Receptors, Muscarinic