Atipamezole, an alpha 2 antagonist, stabilizes age-related high-voltage spindle and passive avoidance defects.
The present study investigates the effects of an alpha 2 antagonist, atipamezole (Ati), on the high-voltage spindle (HVS; Ati at 0.1, 1.0, and 3.0 mg/kg) activity, passive avoidance retention (PA; Ati at 3 mg/kg; injected before retention trial), and water maze (WM; Ati at 3 mg/kg; injected after daily training trials) acquisition of young and aged rats. PA retention trial performance defect of aged rats was partially alleviated by Ati at a 3-mg/kg dose. Ati at 3 mg/kg had no effect on the PA performance of young rats. Retention trial performance of nonshocked young or aged rats was not altered by a 3-mg/kg Ati dose. WM acquisition was not affected by posttraining Ati injections. Age-related increase of HVS was stabilized by Ati at 1 or 3 mg/kg. Ati at 1 and 3 mg/kg completely suppressed HVS of young rats. Ati at 0.1 mg/kg had no effect on HVS of young or aged rats. The results suggest that alpha 2-antagonist-administration-induced increase in noradrenergic activity may stabilize age-related HVS activity increase and PA performance defect.
Department of Neurology, University of Kuopio, Finland.
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P
Riekkinen
J
J
Sirviö
M
M
Riekkinen
R
R
Lammintausta
P
P
Riekkinen
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000375:Aging / Q000523:psychology*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects* / Q000502:physiology; D003071:Cognition / Q000187:drug effects / Q000502:physiology; D005260:Female; D007093:Imidazoles / Q000494:pharmacology*; D008125:Locus Coeruleus / Q000187:drug effects / Q000502:physiology; D008568:Memory / Q000187:drug effects / Q000502:physiology; D051381:Rats
D000317:Adrenergic alpha-Antagonists; D007093:Imidazoles; C050701:atipamezole