The addition of neostigmine did not reverse the muscle relaxation induced by suxamethonium. Which one of the following statements regarding the effect of neostigmine on suxamethonium best explains this? Suxamethonium is a more potent acetylcholinesterase inhibitor than neostigmine and so prevents an increase in ACh levels. Neostigmine blocks the degradation of suxamethonium by binding to plasma (pseudo) cholinesterase. Because suxamethonium is an agonist, only a competitive reversible antagonist can reverse its actions. Suxamethonium prevents neostigmine from binding to the nicotinic receptors present on the skeletal muscle. By enhancing ACh levels, neostigmine perpetuates the maintained stimulation of nicotinic receptors responsible for the muscle relaxation.
Added by Daniel D.
Close
Step 1
This means that neostigmine was not able to counteract the effects of suxamethonium. Option A is incorrect because it suggests that suxamethonium is a more potent acetylcholinesterase inhibitor than neostigmine, which is not true. In fact, neostigmine is a more Show more…
Show all steps
Your feedback will help us improve your experience
Sri K and 54 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
If astroglia were absent, how might the effects of acetylcholine be affected? a) Less ACh would be produced b) Reuptake of ACh would be inhibited c) Diffusion of ACh would likely be increased d) More ACh would be produced In an ionotropic receptor, which of the following is FALSE regarding ligand binding? (Reminder: Ligand = chemical messengers such as neurotransmitters) a) Ligands bind on the intracellular space of the postsynaptic neuron b) Ligand binding triggers protein conformational changes c) Ligand binding occurs outside of the cell membrane d) Ligands cannot bind without the actions of Ca2+
Fatina S.
When considering the effects of norepinephrine, which of the following would account for the observed change in heart rate? (Please choose all answers that apply.) Increased activation of beta 2 receptors An increase in cAMP A decrease in K+ efflux A decrease in cAMP Threshold is reached sooner An increase in K+ influx A decrease in phospholamban activity Ca2+ channels are open longer A reduction in the duration of the pacemaker potential A reduction in Ca2+ permeability
Sri K.
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD