S-Space College of Medicine/School of Medicine (의과대학/대학원) Surgery (외과학전공) Journal Papers (저널논문_외과학전공)
Sulfur-containing amino acids block stretch-dependent K+ channels and nitrergic responses in the murine colon
- Park, Kyu Joo; Baker, Salah A; Cho, Sang Yun; Sanders, Kenton M; Koh, Sang Don
- Issue Date
- Nature Publishing Group
- Br J Pharmacol. 2005 Apr;144(8):1126-37
- Amino Acids/*pharmacology; Animals; Colon/*drug effects/physiology; Female; Male; Mice; Mice, Inbred BALB C; Nitrergic Neurons/*drug effects/physiology; Potassium Channel Blockers/*pharmacology; Potassium Channels/*physiology; Sulfur Compounds/*pharmacology
- 1. Efforts to determine the role of stretch-dependent K(+) (SDK) channels in enteric inhibitory neural responses in gastrointestinal muscles are difficult due to a lack of blocking drugs for SDK channels. 2. SDK channels are blocked by sulfur-containing amino acids. These compounds reduced the open probability of SDK channels in on and off-cell patches of murine colonic myocytes. L-Methionine was the most selective and had little or no effect on other known K(+) conductances in colonic myocytes. 3. Application of L-cysteine, L-methionine or DL-homocysteine depolarized intact muscles and enhanced spontaneous contractions. D-Stereoisomers of these amino acids were less effective than L-stereoisomers. 4. Pretreatment of muscles with tetrodotoxin, N(W)-nitro-L-arginine or 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one reduced the depolarization responses to these compounds, suggesting that spontaneous neural activity and release of NO tonically activates SDK channels. 5. Nitrergic responses to nerve stimulation were reduced by sulfur-containing amino acids. 6. These data suggest that nitrergic inhibitory junction potentials are mediated, in part, by activation of SDK channels in murine colonic muscles.
- 0007-1188 (Print)
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