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What is Antiparkinsonian drug activating D2 receptors directly and explain in detail?
Direct D2 activators are bromcriptine , pergolide,pramipexole,ropinirole. ENtcapone and tolcapone are COMT inhibitors and selegiline is a MAO inbibitor used in PD.In PD there is decrease of dopamine in the substansia nigra. Ref:KDT 6/e p419