ToxSci Advance Access originally published online on October 20, 2004
Toxicological Sciences 2005 83(1):149-154; doi:10.1093/toxsci/kfi010
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Toxicological Sciences vol. 83 no. 1 © Society of Toxicology 2005; all rights reserved.
Effects of Trichloroethylene and Perchloroethylene on Muscle Contractile Responses and Epithelial Prostaglandin Release and Acetylcholinesterase Activity in Swine Trachea

* Institute of Pharmacology and Toxicology, Tzu Chi University No 701, Section 3, Hualien 970, Taiwan;
Institute of Medical Sciences, Tzu Chi University No 701, Section 3, Hualien 970, Taiwan; and
Department of Pharmacology, Tzu Chi University No 701, Section 3, Hualien 970, Taiwan
Received May 20, 2004; accepted September 6, 2004
Trichloroethylene (TCE) and perchloroethylene (PERC) have been reported to induce respiratory complications such as airway hyperactivity and asthma. The present study was designed to investigate their influence on smooth muscle contraction and epithelial release of prostanoids in swine trachea. Results showed that TCE and PERC exposure did not alter the basal tone of tracheal smooth muscle. However, TCE and PERC concentration-dependently increased both ACh-induced and high K+-induced muscle contraction. In addition to potentiation of muscle contractile responses evoked by acetylcholine or histamine, pretreatment of smooth muscle with PERC at higher concentration significantly suppressed the relaxant activity of beta-adrenergic agonists. The epithelial prostaglandin (PG)E2, but not PGD2, release from tracheal epithelium was significantly increased by TCE and PERC. In addition, the acetylcholinesterse (AChE) activity of tracheal epithelia was reduced by TCE and PERC. In conclusion, our results suggest that the enhancement of spasmogen-evoked muscle contractile responses and epithelial PGE2 secretion, as well as reduction of epithelial AChE activity, may participate in airway impairment and hyperresponsiveness after TCE and PERC exposure.
Key Words: tricholoroethylene; perchloroethylene; trachea; swine; prostaglandin; acetylcholinesterase.