On the mechanism which mediates the effects of long-term administration of fencamfamine in rats.
This study analyzes the changes in the sensitivity of striatal dopaminergic (DA) receptors to apomorphine following withdrawal from long-term treatment with fencamfamine (10 mg/kg, for 40 days). Fencamfamine treatment decreased (34.8 +/- 3.2 vs 25.8 +/- 2.8, P less than 0.05) the stereotyped behavior induced by apomorphine (2.0 mg/kg, sc), but potentiated the effect of apomorphine (0.02 mg/kg, sc) in reducing the striatal levels of homovanillic acid (HVA) (0.41 +/- 0.02 micrograms/g vs 0.31 +/- 0.03 micrograms/g, P less than 0.01) and dihydroxyphenylacetic acid (DOPAC) (0.45 +/- 0.04 micrograms/g vs 0.34 +/- 0.03 micrograms/g, P less than 0.01). These results suggest that changes in pre- or postsynaptic DA receptors may underlie the tolerance and sensitization to the effects of fencamfamine.
Planeta
C S
CS
Departamento de Farmacologia, Universidade de São Paulo, Brasil.
DeLucia
R
R
Aizenstein
M L
ML
Scavone
C
C
D000818:Animals; D001058:Apomorphine / Q000037:antagonists & inhibitors*; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D003342:Corpus Striatum / Q000187:drug effects; D004344:Drug Incompatibility; D004361:Drug Tolerance; D008297:Male; D009636:Norbornanes / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects; D013239:Stereotyped Behavior / Q000187:drug effects*
D000697:Central Nervous System Stimulants; D009636:Norbornanes; D011954:Receptors, Dopamine; D001058:Apomorphine; C020900:fencamfamine