Behavioral Sensitization to Apomorphine in Pigeons
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چکیده
Repeated administration of apomorphine leads to a context-dependent pecking response sens iti zation . Previously sens itized pigeons (Co /llmba /ivia) challenged with saline in the same context show a conditioned response (CR) . The authors studied the effects of intra striatal inj ections of the dopamine (D, ) antagonist SCH-23390 on both the sensiti zed response and the C R. When coadministcred with apomorphine, SCH-23390 inhibited the initial rcsponsc to apomorphine, prevented the development of sens itization , and impaired the maintenance of an already developed sens itization . However, SCH-23390 had no effcct on the rctricval ofa previously establi shed CR. It is concluded that the activation of D , receptors in the caudal avian striatum is necessary for the acquisition and maintenance of the sens iti zation, but not for the express ion, of the CR.
منابع مشابه
Long-term behavioral sensitization to apomorphine is independent of conditioning and increases conditioned pecking, but not preference, in pigeons.
When rodents are given a free choice between a variable option and a constant option, they may prefer variability. This preference is even sometimes increased following repeated administration of a dopamine agonist. The present study was the first to examine preference for variability under the systemic administration of a dopamine agonist, apomorphine (Apo), in birds. Experiment 1 tested the d...
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