Abstract
Mouse myotubes were used to investigate effects of the nondepolarizing neuromuscular blocking drugs pancuronium and atracurium on embryonic-type nicotinic acetylcholine receptor channels. Experiments were performed using patch-clamp techniques in combination with devices for ultra-fast solution exchange at outside-out patches. Application of 0.1 mM acetylcholine resulted in a fast current transient. When the peak amplitude was achieved, the current decayed monoexponentially due to desensitization. After application of drugs (pancuronium or atracurium), two different mechanisms of block were observed: (1) open channel block of embryonic-type nicotinic acetylcholine receptor channels after coapplication of blocker and acetylcholine, characterized by decrease of the time constant of current decay; (2) competitive block of embryonic-type nicotinic acetylcholine receptor channels by pancuronium or atracurium after preincubation of outside-out patches with the respective blocker. Different affinities of pancuronium (KB≈0.01 μM) and atracurium (KB≈1 μM) to embryonic-type nicotinic acetylcholine receptor channels were observed.
| Original language | English |
|---|---|
| Pages (from-to) | 31-35 |
| Number of pages | 5 |
| Journal | European Journal of Pharmacology |
| Volume | 413 |
| Issue number | 1 |
| DOIs | |
| State | Published - 9 Feb 2001 |
Keywords
- Atracurium
- Competitive block
- Embryonic-type
- Nicotinic receptor channel
- Open channel block
- Pancuronium