the response of motoneurones to direct current pulse injection or synaptic excitation was investigated following intravenous injection of l-beta-3,4-dihydroxyphenylalanine ( l-dopa , 20-120 mg/kg ) alone , nialamide ( 10-50 mg/kg ) and l-dopa or clonidine ( 0.5-1 mg/kg ) .
C0013023
dihydroxyphenylalanine
C0023570
l-dopa