Inhibitory effect of suberogorgin on acetylcholinesterase.

AIM: To study the selection, reversibility, and kinetics of suberogorgin (Sub) on acetylcholinesterase (AChE). METHODS: The human plasma was used as butyrylcholinesterase (BuChE). The activity of ChE was determined with colorimetry. RESULTS: Sub obviously inhibited the AChE in vitro with pl50 4.03, 4.92, 3.82, and 4.67 in RBC membranes (of rat and human) and tissue extracts (of rat brain and earthworm dorsal muscle), respectively. No inhibition on BuChE was observed. The inhibition of Sub on AChE was far lower than that of physostigmine, but was close to that of galanthamine. Sub decreased the AChE activity to the lowest within 3 min after it was incubated with AChE. Centrifugalization washing reactivated the AChE which had been inhibited by Sub. The double-reciprocal plots of different concentrations of Sub on AChE showed parallel lines. CONCLUSION: Sub was a selective, reversible, and contra-competetive inhibitor of AChE at the binding site on the peripheral anion region of AChE.