On the role of brain noradrenaline and the pituitary-adrenal axis in avoidance learning. I. Studies with corticosterone.
A marked impairment of the acquisition of a one-way active avoidance response was observed in rats after a 6-hydroxydopamine-induced lesion of the ascending (dorsal) noradrenaline bundle to the cortex cerebri in combination with adrenalectomy. The deficit in acquisition was prevented by low daily doses of corticosterone. Neither adrenalectomy nor lesions of the dorsal noradrenaline bundle alone caused a deficit. It is suggested that brain noradrenaline neurons and the pituitary-adrenal axis may interact in the control of active avoidance behavior. Finally, noradrenaline neurons appear not to play any role in extinvtion of punished behavior.
Ogren
S O
SO
Research and Development Laboratories, Astra Pharmaceuticals, Södertälje, Karolinska Institutet, Stockholm, Sweden.
Fuxe
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K