In vivo
How does the nicotinic receptor activate skeletal muscle contraction?
- When acetylcholine or nicotine binds na+ channels open and na+ flows into the cell,
causing a depolarization. This has an excitatory effect on skeletal muscle.
What is the effect of the beta-blocker propranolol on blood pressure? Explain your
answer.
- Propanolol lowers the blood pressure by occuping the beta receptor so that in
cannot be activated, this ultimately prevents less ca2+ to flow into the cell and
induce contractions.
What is the effect of the alpha-blocker phentolamine on blood pressure? Explain your
answer.
- Phentolamine produces its therapeutic actions by competitively blocking alpha-
adrenergic receptors (primarily excitatory responses of smooth muscle and exocrine
glands), leading to a muscle relaxation and a widening of the blood vessels. This
widening of the blood vessels results in a lowering of blood pressure.
How is the muscarinic 2 receptor coupled?
- Gi
What type of receptor is the nicotinic receptor on the skeletal muscle?
- Ligand gated ion channels
What is the effect of agonism of the presynaptic α2 receptor on blood pressure?
- The lowering of the blood pressure
What is an acetylcholinesterase inhibitor? Give an example of an compound that is an
acetylcholinesterase inhibitor. Does this compound affect muscle contraction/relaxation
and, if so, how?
- An acetylcholinesterase inhibitor inhibits the enzyme acetylcholinesterase
responsible for the breakdown of acetylcholine. thereby increasing both the level
and duration of action of acetylcholine in the central nervous system, autonomic
ganglia and neuromuscular junctions,
What is the effect of the α1 receptor activation in the blood vessels?
They determine both arteriolar resistance and venous capacitance, and thus blood pressure.
How does the nicotinic receptor activate skeletal muscle contraction?
- When acetylcholine or nicotine binds na+ channels open and na+ flows into the cell,
causing a depolarization. This has an excitatory effect on skeletal muscle.
What is the effect of the beta-blocker propranolol on blood pressure? Explain your
answer.
- Propanolol lowers the blood pressure by occuping the beta receptor so that in
cannot be activated, this ultimately prevents less ca2+ to flow into the cell and
induce contractions.
What is the effect of the alpha-blocker phentolamine on blood pressure? Explain your
answer.
- Phentolamine produces its therapeutic actions by competitively blocking alpha-
adrenergic receptors (primarily excitatory responses of smooth muscle and exocrine
glands), leading to a muscle relaxation and a widening of the blood vessels. This
widening of the blood vessels results in a lowering of blood pressure.
How is the muscarinic 2 receptor coupled?
- Gi
What type of receptor is the nicotinic receptor on the skeletal muscle?
- Ligand gated ion channels
What is the effect of agonism of the presynaptic α2 receptor on blood pressure?
- The lowering of the blood pressure
What is an acetylcholinesterase inhibitor? Give an example of an compound that is an
acetylcholinesterase inhibitor. Does this compound affect muscle contraction/relaxation
and, if so, how?
- An acetylcholinesterase inhibitor inhibits the enzyme acetylcholinesterase
responsible for the breakdown of acetylcholine. thereby increasing both the level
and duration of action of acetylcholine in the central nervous system, autonomic
ganglia and neuromuscular junctions,
What is the effect of the α1 receptor activation in the blood vessels?
They determine both arteriolar resistance and venous capacitance, and thus blood pressure.
