Actions of levodopa on the blood pressure of conscious rabbits.

1. In conscious rabbits, the rapid intravenous injection of levodopa alone does not have any significant effects on the blood pressure in doses up to 10 mg/kg.2. After inhibition of monoamine oxidase, levodopa induces a sustained pressor response.3. This response can be blocked by inhibition of extracerebral decarboxylase.4. Possible mechanisms for these interactions are discussed, together with their therapeutic implications in Parkinsonism.