Stimulation of Na+,K+-ATPase activity in certain membranes of the rat central nervous system (CNS) by acute administration of desipramine (DMI).
1. The activities of ATPase in rat CNS were studied 3 hr after administration of the noradrenaline uptake inhibitor, desipramine (DMI: 10 mg.kg-1, i.p.). Na+K+-ATPase activity significantly increased after DMI in the whole particulate from hypothalamus and mesencephalus but no changes in frontal cortex or in pons-medulla oblongata areas were found. This increase was prevented when the animals were pretreated with the noradrenergic neurotoxic N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4). 2. Purified membrane fractions from hypothalamus were obtained by differential and sucrose gradient centrifugation (0.8-1.2 M sucrose). It was observed that after DMI, Na+,K+-ATPase activity increased only in the membranous fraction lying at 0.9 M sucrose. 3. Mg2+- or Ca2+-ATPase activities were not modified by DMI treatment. 4. Citalopram, a specific serotonergic uptake inhibitor, did not affect ATPase activities. 5. The results obtained could indicate that DMI acute administration selectively stimulates Na+,K+-ATPase activity of certain membranes of the CNS after an increase in the concentration of the noradrenergic neurotransmitter in the synaptic gap.
Viola
M S
MS
Cátedra de Farmacología-Facultad de Farmacia y Bioquímica, UBA, Argentina.
Bojorge
G
G
Rodriguez de Lores Arnaiz
G
G
Enero
M A
MA
D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000201:enzymology; D003891:Desipramine / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D005625:Frontal Lobe / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D007031:Hypothalamus / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D008297:Male; D008526:Medulla Oblongata / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D008566:Membranes / Q000187:drug effects* / Q000201:enzymology; D008636:Mesencephalon / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D051381:Rats; D011919:Rats, Inbred Strains; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*
D000254:Sodium-Potassium-Exchanging ATPase; D003891:Desipramine