Lead neurotoxicity: a role for dopamine receptors.
Chronic lead exposure differentially affects dopamine receptor subtypes (D1 and D2). In particular dopamine D2 recognition sites in striatum are up-regulated while in nucleus accumbens they are down-regulated. These changes may be correlated to the observed alterations of dopamine terminal activity. Consistent with these biochemical changes behavioral studies indicate that lead-treated rats show more pronounced basal activity, attenuation of apomorphine (63 micrograms/kg s.c.) induced hypomotility and tendency to increased stereotyped response to apomorphine (300 micrograms/kg s.c.). On the contrary, both behavioral and biochemical markers of D1 receptors are unmodified by lead treatment. In fact, SKF 38393-induced grooming behavior, [3H]SCH 23390 binding and the dopamine stimulated adenylate cyclase activity are comparable in controls and lead-exposed rats.
Moresco
R M
RM
Institute of Pharmacological Sciences, University of Milan, Italy.
Dall'Olio
R
R
Gandolfi
O
O
Govoni
S
S
Di Giovine
S
S
Trabucchi
M
M
D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects*; D001552:Benzazepines / Q000378:metabolism / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D005260:Female; D007855:Lead Poisoning / Q000378:metabolism*; D008297:Male; D008431:Maternal-Fetal Exchange; D009714:Nucleus Accumbens / Q000187:drug effects; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects*; D014316:Tritium
D001552:Benzazepines; D011954:Receptors, Dopamine; D014316:Tritium; D015647:2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine; D001058:Apomorphine