Peripherally administered substance P affects extracellular dopamine concentrations in the neostriatum but not in the nucleus accumbens under anesthesia.
The in situ microdialysis technique was used in urethane-anesthetized rats to monitor changes in the extracellular concentrations of dopamine and its metabolites in neostriatum and nucleus accumbens after the peripheral administration of substance P (50 or 250 micrograms/kg, IP). Four to five hours after urethane anesthesia a decrease of extracellular dopamine and its metabolites was observed which continued in the nucleus accumbens in the following 3 h. The administration of substance P induced a decrease in extracellular concentration of dopamine in neostriatum. This neurochemical change after substance P was not accompanied by parallel alterations in extracellular concentrations of dopamine metabolites. No effects of substance P were observed on dopamine or its metabolites in nucleus accumbens. These data are discussed in relation with the contrasting effects of substance P on awake rats and the possible changes in striatal dopamine activity induced by anesthetics.
Boix
F
F
Institute of Physiological Psychology I, University of Düsseldorf, Germany.
Mattioli
R
R
Adams
F
F
Huston
J P
JP
Schwarting
R K
RK
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D003956:Dialysis; D004298:Dopamine / Q000378:metabolism*; D006719:Homovanillic Acid / Q000378:metabolism; D007274:Injections, Intraperitoneal; D008297:Male; D008846:Micromanipulation; D017072:Neostriatum / Q000187:drug effects* / Q000378:metabolism; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013373:Substance P / Q000008:administration & dosage / Q000494:pharmacology*; D014520:Urethane
D015102:3,4-Dihydroxyphenylacetic Acid; D013373:Substance P; D014520:Urethane; D004298:Dopamine; D006719:Homovanillic Acid