Summary
The thermal cutaneous evoked tail flick response was measured both before and after intrathecal injection of R-apomorphine in spinal rats and in rats with an intact neuraxis pretreated with either long-term haloperidol or intrathecal 6-hydroxydopamine. Intrathecal R-apomorphine produced a dose-dependent increase of tail flick latency in spinal rats but not in intact rats. Long-term haloperidol treatment increased the effect of R-apomorphine in spinal rats while 6-OHDA decreased it. The present findings provide further evidence for the modulatory role of spinal DA receptor populations on spinal reflex activity. Pretreatment with long-term haloperidol or 6-OHDA may alter the conformational status of spinal DA receptors in opposite directions and thereby change the responsiveness of receptors to R-apomorphine.
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Jensen, T.S., Christensen, N.J. & Smith, D.F. Differential effects of apomorphine on spinal reflex activity following 6-hydroxydopamine or long-term haloperidol pretreatment. J. Neural Transmission 65, 125–134 (1986). https://doi.org/10.1007/BF01256488
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DOI: https://doi.org/10.1007/BF01256488