Abstract
Contraction and electrophysiological effects of 5-methylfurmethiodide (MFI), a selective muscarinic agonist in mammals, were tested on Ascaris suum muscle strips. In a contraction assay, MFI produced weak contraction and was less potent than levamisole and acetylcholine. Atropine (3microM) a non-selective muscarinic antagonist in mammalian preparations, did not affect contractions produced by MFI. Mecamylamine (3microM) a nicotinic antagonist in A. suum preparations, blocked the MFI contractions indicating that MFI had weak nicotinic agonist actions. In two-micropipette current-clamp experiments MFI, at concentrations greater than 10microM, produced concentration-dependent depolarizations and small increases in membrane conductance. The depolarizing effects were not abolished by perfusing the preparation in a calcium-free Ascaris Ringer solution to block synaptic transmission, suggesting that MFI effects were mediated by receptors on the muscle and were calcium-independent. A high concentration of mecamylamine, 30microM, only reduced the depolarizing responses by 42%, indicating that MFI also had effects on non-nicotinic receptors. Three non-nicotinic effects in the presence of 30microM mecamylamine were identified using voltag...Continue Reading
References
Sep 21, 1990·European Journal of Pharmacology·K E Roberts, N R Newberry
Dec 1, 1987·British Journal of Pharmacology·N R Newberry, T Priestley
Sep 1, 1971·The Journal of Physiology·A F Brading, P C Caldwell
Feb 1, 1970·British Journal of Pharmacology·M L AubryS Shevde
May 1, 1970·British Journal of Pharmacology·J AcevesR Martínez-Marañón
Oct 1, 1982·British Journal of Pharmacology·R J Martin
Dec 27, 1994·European Journal of Pharmacology·S J RobertsonR J Martin
May 1, 1995·Parasitology·V M Dale, R J Martin
Jan 1, 1993·British Journal of Pharmacology·S J Robertson, R J Martin
Jun 15, 1994·The Journal of Physiology·M P CaulfieldD A Brown
Feb 1, 1993·The Journal of General Physiology·M A Segerberg, A O Stretton
Jul 1, 1996·British Journal of Pharmacology·A M Evans, R J Martin
Nov 1, 1996·Experimental Physiology·R J Martin, M A Valkanov
Oct 18, 2000·Journal of Neurochemistry·Y S LeeN J Cho
Apr 18, 2001·The Journal of Physiology·K MellitiB A Adams
Jul 18, 2002·Parasitology·J PurcellR J Martin
Aug 17, 2002·The Journal of Pharmacology and Experimental Therapeutics·Alan P RobertsonRichard J Martin
Dec 10, 2003·British Journal of Pharmacology·Alexander V ZholosTom B Bolton
Jul 9, 2004·Genetics·Katherine A Steger, Leon Avery
Jul 24, 2004·The Journal of Physiology·D J BeechR Flemming
Jul 24, 2004·The Journal of Physiology·Yoshiko TakaiAkira Takai
Oct 1, 2005·The Journal of Physiology·A P Albert, W A Large
Feb 8, 2006·Annual Review of Physiology·I Scott RamseyDavid E Clapham
Oct 24, 2006·FASEB Journal : Official Publication of the Federation of American Societies for Experimental Biology·Hai QianAlan P Robertson
Feb 9, 2007·The Journal of Neuroscience : the Official Journal of the Society for Neuroscience·Yishi LiuL René Garcia
May 24, 2007·British Journal of Pharmacology·S VermaR J Martin
Jul 5, 2007·Parasitology·R J Martin, A P Robertson
Citations
Apr 9, 2013·Parasitology International·A P RobertsonR J Martin
Jul 23, 2015·International Journal for Parasitology. Drugs and Drug Resistance·Ben-Wen LiGary J Weil
Jul 16, 2021·Scientific Reports·Sudhanva S KashyapRichard J Martin
Jan 21, 2017·Research in Veterinary Science·Saša M TrailovićJelena Nedeljković Trailović