Glucocorticoid modification of spinal dopamine receptor activation by apomorphine
Abstract:
The effects of an intensive short-term glucocorticoid (e.g. triamcinolone) regimen in cats have been studied on the actions of the dopamine (DA) receptor agonist apomorphine (APO) on spinal lumbar primary afferent excitability (dorsal root reflex or DRR) and monosynaptic reflex (MSR) transmission. Glucocorticoid dosing significantly decreased the APO-induced depression of the spinal DRR, but not the similar action of APO on the MSR. This complex effect of triamcinolone on spinal dopaminergic activation by APO may represent a differential action of glucocorticoid on two types of spinal DA receptors with one type, but not the other, undergoing partial desensitization.
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