Final answer:
To decrease skeletal muscle cramps, muscle relaxants acting as antagonists are used, while smooth muscle cramps are treated with antispasmodics acting as antagonists. Botulinum toxin is an antagonist example that inhibits ACh release. The antidote to atropine poisoning is a muscarinic agonist.
Step-by-step explanation:
To decrease skeletal and smooth muscle cramps, one can use either agonists or antagonists. An agonist is a substance that activates a receptor to produce a biological response, while an antagonist blocks the receptor and prevents the response. In the case of skeletal muscle cramps, medications like muscle relaxants are often used as antagonists to decrease muscle tension and spasms. They might function by inhibiting the release of neurotransmitters or by inhibiting muscle fiber excitation.
For smooth muscle cramps, such as those occurring in the gastrointestinal tract, antispasmodics like dicyclomine or hyoscine butylbromide can be used. These work by inhibiting the action of acetylcholine on muscarinic receptors, acting as antagonists.
An example of a medication that acts as an antagonist at the neuromuscular junction is botulinum toxin, which inhibits the release of acetylcholine (ACh), thereby reducing muscle contractions. Conversely, in myasthenia gravis, a disease characterized by muscle weakness, the body's immune response impairs the function of ACh receptors at the neuromuscular junction, demonstrating how crucial the role of neurotransmitter agonists is in maintaining normal muscle function.
Answering the multiple-choice questions:
- The type of drug that would be an antidote to atropine poisoning is a muscarinic agonist (c.).
- A kind of drug that would have anti-anxiety effects might be an antagonist to certain neurotransmitters that are associated with anxiety.