Electrophysiological Properties of Ion Channels in Ascaris suum Tissue Incorporated into Planar Lipid Bilayers
10.3347/kjp.2021.59.4.329
- Author:
Kwon Moo PARK
1
;
Sun-Don KIM
;
Jin Bong PARK
;
Sung-Jong HONG
;
Pan Dong RYU
Author Information
1. Department of Veterinary Pharmacology, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
- Publication Type:Original Article
- From:The Korean Journal of Parasitology
2021;59(4):329-339
- CountryRepublic of Korea
- Language:English
-
Abstract:
Ion channels are important targets of anthelmintic agents. In this study, we identified 3 types of ion channels in Ascaris suum tissue incorporated into planar lipid bilayers using an electrophysiological technique. The most frequent channel was a large-conductance cation channel (209 pS), which accounted for 64.5% of channels incorporated (n=60). Its open-state probability (Po) was ~0.3 in the voltage range of –60~+60 mV. A substate was observed at 55% of the main-state. The permeability ratio of Cl- to K+ (PCl/PK) was ~0.5 and PNa/PK was 0.81 in both states. Another type of cation channel was recorded in 7.5% of channels incorporated (n=7) and discriminated from the large-conductance cation channel by its smaller conductance (55.3 pS). Its Po was low at all voltages tested (~0.1). The third type was an anion channel recorded in 27.9% of channels incorporated (n=26). Its conductance was 39.0 pS and PCl/PK was 8.6±0.8. Po was ~1.0 at all tested potentials. In summary, we identified 2 types of cation and 1 type of anion channels in Ascaris suum. Gating of these channels did not much vary with voltage and their ionic selectivity is rather low. Their molecular nature, functions, and potentials as anthelmintic drug targets remain to be studied further.
