Evaluation of Na+, K+-ATPase activity in the brain of young rats after acute administration of fenproporex.
OBJECTIVE
Fenproporex is an amphetamine-based anorectic which is rapidly converted into amphetamine in vivo. Na+, K+-ATPase is a membrane-bound enzyme necessary to maintain neuronal excitability. Considering that the effects of fenproporex on brain metabolism are poorly known and that Na+, K+-ATPase is essential for normal brain function, this study sought to evaluate the effect of this drug on Na+, K+-ATPase activity in the hippocampus, hypothalamus, prefrontal cortex, and striatum of young rats.


METHODS
Young male Wistar rats received a single injection of fenproporex (6.25, 12.5, or 25 mg/kg intraperitoneally) or polysorbate 80 (control group). Two hours after the last injection, the rats were killed by decapitation and the brain was removed for evaluation of Na+, K+-ATPase activity.


RESULTS
Fenproporex decreased Na+, K+-ATPase activity in the striatum of young rats at doses of 6.25, 12.5, and 25 mg/kg and increased enzyme activity in the hypothalamus at the same doses. Na+, K+-ATPase activity was not affected in the hippocampus or prefrontal cortex.


CONCLUSIONS
Fenproporex administration decreased Na+, K+-ATPase activity in the striatum even in low doses. However, in the hypothalamus, Na+, K+-ATPase activity was increased. Changes in this enzyme might be the result of the effects of fenproporex on neuronal excitability.
Laboratory of Experimental Pathophysiology, Graduate Program in Health Sciences, Universidade do Sul de Santa Catarina, Tubarão, SC, Brazil.
Gislaine T
GT
Rezin
Laboratory of Bioenergetics, Graduate Program in Health Sciences, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
Giselli
G
Scaini
Laboratory of Bioenergetics, Graduate Program in Health Sciences, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
Cinara L
CL
Gonçalves
Laboratory of Bioenergetics, Graduate Program in Health Sciences, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
Gabriela K
GK
Ferreira
Laboratory of Bioenergetics, Graduate Program in Health Sciences, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
Mariane R
MR
Cardoso
Laboratory of Neuroprotection and Metabolic Diseases, Department of Biochemistry, Institute for Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Andréa G K
AG
Ferreira
Laboratory of Neuroprotection and Metabolic Diseases, Department of Biochemistry, Institute for Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Maira J
MJ
Cunha
Laboratory of Neuroprotection and Metabolic Diseases, Department of Biochemistry, Institute for Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Felipe
F
Schmitz
National Science and Technology Institute for Translational Medicine, Brazil.
Roger B
RB
Varela
National Science and Technology Institute for Translational Medicine, Brazil.
João
J
Quevedo
Laboratory of Neuroprotection and Metabolic Diseases, Department of Biochemistry, Institute for Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Angela T S
AT
Wyse
Laboratory of Bioenergetics, Graduate Program in Health Sciences, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
Emilio L
EL
Streck
D000662:Amphetamines / Q000008:administration & dosage*; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000201:enzymology*; D007274:Injections, Intraperitoneal; D008297:Male; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013997:Time Factors
D000662:Amphetamines; D000254:Sodium-Potassium-Exchanging ATPase; C026013:fenproporex