AIM: To investigate the presynaptic effects of propofol, a short-acting intravenous anesthetic, in the frog neuromuscular junction. METHODS: Frog cutaneous pectoris nerve muscle preparations were prepared. A fluorescent tool (FM1-43) was used to visualize the effect of propofol on synaptic vesicle exocytosos in the frog neuromuscular junction. RESULTS: Low concentrations of propofol, ranging from 10 to 25 μmol/L, enhanced spontaneous vesicle exocytosis monitored by FM1-43 in a Ca(2+)-dependent and Na(+)-independent fashion. Higher concentrations of propofol (50, 100, and 200 μmol/L) had no effect on spontaneous exocytosis. By contrast, higher concentrations of propofol inhibited the Na(+)-dependent exocytosis evoked by 4-aminopyridine but did not affect the Na(+)-independent exocytosis evoked by KCl. This action was similar and non-additive with that observed by tetrodotoxin, a Na(+) channel blocker. CONCLUSION: Our data suggest that propofol has a dose-dependent presynaptic effect at the neuromuscular transmission which may help to understand some of the clinical effects of this agent on neuromuscular function.
AIM: To investigate the presynaptic effects of propofol, a short-acting intravenous anesthetic, in the frog neuromuscular junction. METHODS: Frog cutaneous pectoris nerve muscle preparations were prepared. A fluorescent tool (FM1-43) was used to visualize the effect of propofol on synaptic vesicle exocytosos in the frog neuromuscular junction. RESULTS: Low concentrations of propofol, ranging from 10 to 25 μmol/L, enhanced spontaneous vesicle exocytosis monitored by FM1-43 in a Ca(2+)-dependent and Na(+)-independent fashion. Higher concentrations of propofol (50, 100, and 200 μmol/L) had no effect on spontaneous exocytosis. By contrast, higher concentrations of propofol inhibited the Na(+)-dependent exocytosis evoked by 4-aminopyridine but did not affect the Na(+)-independent exocytosis evoked by KCl. This action was similar and non-additive with that observed by tetrodotoxin, a Na(+) channel blocker. CONCLUSION: Our data suggest that propofol has a dose-dependent presynaptic effect at the neuromuscular transmission which may help to understand some of the clinical effects of this agent on neuromuscular function.
Authors: Hugh C Hemmings; Myles H Akabas; Peter A Goldstein; James R Trudell; Beverley A Orser; Neil L Harrison Journal: Trends Pharmacol Sci Date: 2005-10 Impact factor: 14.819
Authors: Kellie A Woll; Stephanie Guzik-Lendrum; Brandon M Bensel; Natarajan V Bhanu; William P Dailey; Benjamin A Garcia; Susan P Gilbert; Roderic G Eckenhoff Journal: J Biol Chem Date: 2018-05-29 Impact factor: 5.157
Authors: Shanker Karunanithi; Drew Cylinder; Deniz Ertekin; Oressia H Zalucki; Leo Marin; Nickolas A Lavidis; Harold L Atwood; Bruno van Swinderen Journal: eNeuro Date: 2020-02-28