Journal of Clinical Toxicology
Open Access

AChE inhibition: One dominant factor for swimming behavior changes of Daphnia magna under DDVP exposure

4^th Global Summit on Toxicology

August 24-26, 2015 Philadelphia, USA

Zongming Ren, Xu Zhang, Xiaoguang Wang, Pingping Qi, Biao Zhang, Yang Zeng and Rongshu Fu

Posters-Accepted Abstracts: J Clin Toxicol

Abstract :

The key enzyme that hydrolyzes the neurotransmitter acetylcholine in cholinergic synapses of both vertebrates and invertebrates,
acetylcholinesterase (AChE) is strongly inhibited by organophosphates. AChE inhibition may induce the decrease of swimming
ability. According to previous research, swimming behavior of different aquatic organisms could be affected by different chemicals,
and there is a shortage of research on direct correlation analysis between swimming behavior and biochemical indicators. Therefore,
swimming behavior and whole-body AChE activity of Daphnia magna under dichlorvos (DDVP) exposure were identified in order to
clarify the relationship between behavioral responses and AChE inhibition in this study. In the beginning, AChE activity was similar
in all treatments with the control. During all exposures, the tendency of AChE activity inhibition was the same as the behavioral
responses of D. magna. The AChE activity of individuals without movement would decrease to about zero in several minutes. The
correlation analysis between swimming behavior of D. magna and AChE activity showed that the stepwise behavioral response was
mainly decided by AChE activity. All of these results suggested that the toxicity characteristics of DDVP as an inhibitor of AChE
on the swimming behavior of organisms were the same, and the AChE activity inhibition could induce loss of the nerve conduction
ability, causing hyperactivity, loss of coordination, convulsions, paralysis and other kinds of behavioral changes, which was illustrated
by the stepwise behavioral responses under different environmental stresses.