Detection of Arginine Amidases Released from Isolated Rabbit Arteries

Abstract

Small amounts of arginine amidolytic activity were found to be released from isolated rabbit arteries. The output of specific arginine amidolytic activity (n mol/min/mg wet weight) from the central ear artery was greater than that from the aorta and that from the pulmonary artery, but the output of lysine amidolytic activity was similar for all three of these arteries. With respect to the time course of the enzyme output, arginine and lysine amidolytic activity in the first time period (0-30 min) was higher than that in each of two later time periods. Electrical stimulation at 4 Hz for 3 minutes had no effect on the output of these amidolytic activities from the isolated rabbit arteries. We confirmed using lima bean trypsin inhibitor (LBTI) affinity adsorption and elution that approximately 30% of arginine amidase activity in the isolated aorta preparation was trypsin-like arginine amidase.