Not an action of bradykinin?

Correct Answer: A

Rationale: Bradykinin is a peptide that causes vasodilation, pain, and an increase in vascular permeability. However, it does not directly cause bronchodilation. This is because bradykinin primarily acts on blood vessels and capillaries, leading to increased blood flow and leakage of fluids, but it does not have a direct effect on the smooth muscle of the bronchioles. Therefore, the correct answer is A. Vasodilation, not bronchodilation. Choices B, C, and D are incorrect because they are all known actions of bradykinin based on its physiological effects.

Correct Answer: C

Rationale: The correct answer is C (Both). Serotonin agonists like buspirone are used as anxiolytics by acting on serotonin receptors. Sumatriptan is used for migraines by constricting blood vessels and blocking pain pathways. Therefore, both options A and B are correct. Option D is incorrect because both buspirone and sumatriptan have clinical uses as serotonin agonists.

Correct Answer: D

Rationale: CNS stimulant agents belong to multiple categories, including respiratory stimulants that increase breathing, psychomotor stimulants that enhance physical activity, and psychomimetic agents that induce hallucinations or altered perceptions. Therefore, the correct answer is D, "All of the above," as CNS stimulants can have effects on various functions in the central nervous system. Choices A, B, and C are incorrect because CNS stimulants do not exclusively belong to any single category, but rather have a broad range of effects on different aspects of brain function.

Correct Answer: A

Rationale: Rationale: Carbamazepine is chemically derived from the tricyclic antidepressant imipramine. It is commonly used as an anti-epileptic medication. Carbamazepine's mechanism of action involves blocking voltage-gated sodium channels in neurons. This helps to stabilize the hyperexcitable neuronal membranes in epilepsy. Ethosuximide and Phenytoin are not derived from tricyclic antidepressants and have different mechanisms of action in treating epilepsy. Therefore, the correct answer is A: Carbamazepine.

Correct Answer: D

Rationale: Step-by-step rationale: 1. Ondansetron is commonly used as an antiemetic, specifically for preventing nausea and vomiting caused by cancer chemotherapy. 2. It works by blocking serotonin receptors in the brain, which helps to alleviate nausea and vomiting. 3. This mechanism of action is specific to antiemetics and not antihistamines, drugs for peptic ulcers, or antiarrhythmics. 4. Therefore, the correct answer is D - Antiemetic for cancer chemotherapy. Summary: - Choice A is incorrect because ondansetron is not an antihistamine. - Choice B is incorrect because ondansetron is not used for treating peptic ulcers. - Choice C is incorrect because ondansetron is not an antiarrhythmic. - The correct answer, D, is supported by the drug's mechanism of action and primary usage as an antiemetic for cancer chemotherapy.