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. 1964 Feb;22(1):72–86. doi: 10.1111/j.1476-5381.1964.tb01545.x

Some observations on the pharmacology of α-methyldopa

M D Day, M J Rand
PMCID: PMC1703913  PMID: 14126060

Abstract

α-Methyldopa in high concentrations impaired the responses of rabbit isolated ileum and guinea-pig isolated vas deferens to stimulation of the sympathetic nerves and to noradrenaline, but these preparations taken from animals previously treated with α-methyldopa showed no sign of impairment. Contractions of the cat nictitating membrane were reduced but not abolished by α-methyldopa. In cats, dogs and rats, pressor responses to noradrenaline were usually slightly increased by α-methyldopa. Pressor responses to tyramine were not affected consistently. α-Methyldopa, α-methyldopamine and α-methylnoradrenaline behaved like dopa, dopamine and noradrenaline respectively in restoring the responses of tissues from reserpine-treated animals to stimulation of the sympathetic nerves to the rabbit ileum, the guinea-pig vas deferens and the cat nictitating membrane and in restoring responses to tyramine of the cat blood pressure and nictitating membrane, and the rat blood pressure. The potency of α-methylnoradrenaline relative to noradrenaline ranged from one-half to one-ninth on various preparations. The results are discussed in relation to the antihypertensive action of α-methyldopa.

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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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