Ontogeny of adenosine uptake sites in guinea pig brain: differential profile of [3H]nitrobenzylthioinosine and [3H]dipyridamole binding sites.
The ontogenetic profile of adenosine uptake sites was investigated in guinea pig cerebral cortex and cerebellum using as ligand probes the uptake inhibitors, [3H]nitrobenzylthioinosine ([3H]NBI) and [3H]dipyridamole ([3H]DPR). In cerebral cortex [3H]NBI binding was highest at E50 and decreased subsequently until P28 while in cerebellum after a first peak at E50 and a subsequent decline it increased again until P28. [3H]DPR binding increased by 25% from E40 to P28 in cerebral cortex while in cerebellum hardly any binding could be detected before E50 and it afterwards increased by more than 250% until P28. Scatchard analysis demonstrated that [3H]NBI labeled approximately as many sites as [3H]DPR in cerebral cortex at E44 while at P28 [3H]DPR labeled more than double as many sites. Accordingly, NBI was more potent in displacing [3H]DPR binding at E44 than at P28. These findings suggest that part of the [3H]DPR binding sites, i.e. the NBI-insensitive one develops later than [3H]NBI binding sites during ontogeny in guinea pig cerebral cortex and cerebellum.
Deckert
J
J
Unit on Neurochemistry, NIMH, Bethesda, MD 20892.
Morgan
P F
PF
Daval
J L
JL
Nakajima
T
T
Marangos
P J
PJ
D000375:Aging; D000818:Animals; D002531:Cerebellum / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism; D002540:Cerebral Cortex / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism; D004176:Dipyridamole / Q000378:metabolism*; D005865:Gestational Age; D006168:Guinea Pigs; D007288:Inosine / Q000031:analogs & derivatives*; D007700:Kinetics; D008566:Membranes / Q000378:metabolism; D011983:Receptors, Purinergic / Q000378:metabolism*; D013868:Thioinosine / Q000031:analogs & derivatives* / Q000378:metabolism
D011983:Receptors, Purinergic; D013868:Thioinosine; D007288:Inosine; D004176:Dipyridamole; C001789:4-nitrobenzylthioinosine