Abstract
Repeated daily administration of an oral dose of 1000 mg of alpha-methyl-dopa (methyl dopa) to conscious dogs produced a conditioned adaptive hypertensive systolic and diastolic arterial pressure response along with the direct hypotensive pharmacological effect. The lower dose of 500 mg/day appeared to be devoid of direct or adaptive response effects, while the higher dose of 2000 mg/day only produced a blood pressure lowering response. The abrupt drug withdrawal unmasking the homeostatic state resulted in a marked systolic and diastolic pressor response which endured for about 10-days with peak effect reached at 17-days after termination of drug treatment. Comparable results were obtained whether the dogs were evaluated while in their normal horizontal body position or in a repositioned upright condition.
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Korol, B., McLaughlin, L.J. A homeostatic adaptive response to alpha-methyl-dopa in conscious dogs. Pav. J. Biol. Sci. 11, 67–75 (1976). https://doi.org/10.1007/BF03000285
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DOI: https://doi.org/10.1007/BF03000285