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. 1975 Jun;54(2):171–179. doi: 10.1111/j.1476-5381.1975.tb06926.x

Alternative approaches to analgesia

Baclofen as a model compound

DA Cutting, CC Jordan
PMCID: PMC1666634  PMID: 1148507

Abstract

1 It is suggested that analgesia could be produced by drug action at the spinal level through (a) interference with neurotransmission at primary afferent terminals; (b) enhancement of the `gate control' of the sensory input to the spinal cord mediated through descending spinal tracts; or (c) increased presynaptic inhibition of primary afferents by a direct action.

2 Baclofen (9.4-70.3 μmol/kg, i.p.), which may mimic spinal presynaptic inhibition, produced a dose-dependent increase in the response times of mice in a hot-plate test, but high doses also impaired motor function.

3 Morphine hydrochloride (5.3-40 μmol/kg, i.p.) increased the response time of mice in the hot-plate test and had little effect on motor function.

4 Combination of baclofen (9.4 or 23.4 μmol/kg) with morphine (13.3 μmol/kg) produced greater increases in response time than either drug administered alone but with little concurrent effect on motor function.

5 The possibility that baclofen may have some analgesic action and a potentiating effect on other analgesics is discussed.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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