discharge of zymogens as measured by the secretion of amylase stimulated with 5 x 10 ( -6 ) m carbamylcholine is reduced by 20 % if 10 mm concentrations of phenylalanine , tryptophane or p-chlorophenylalanine are present in the medium .
C0031453
phenylalanine
C0030135
p-chlorophenylalanine