A 65-year-old male with hypertension is prescribed lisinopril. Lisinopril works by:

Correct Answer: A

Rationale: The correct answer is A. Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor, which works by inhibiting the conversion of angiotensin I to angiotensin II. Angiotensin II is a potent vasoconstrictor that increases blood pressure. By inhibiting its production, lisinopril helps dilate blood vessels, reduce blood pressure, and improve blood flow. This mechanism is crucial in managing hypertension. Choice B is incorrect because beta-blockers, not ACE inhibitors like lisinopril, block beta-adrenergic receptors in the heart to reduce heart rate and blood pressure. Choice C is incorrect because while lisinopril does relax vascular smooth muscle, the primary mechanism is through angiotensin II inhibition. Choice D is incorrect because lisinopril does not directly affect sodium excretion in the kidneys; instead, it primarily targets the renin-angiotensin-aldosterone system to regulate blood

Correct Answer: B

Rationale: The correct answer is B: Warfarin. Warfarin is a commonly used anticoagulant that helps prevent thromboembolic events in atrial fibrillation by inhibiting the clotting factors. It is recommended for patients with atrial fibrillation to reduce the risk of stroke. Heparin is typically used for acute treatment, not long-term prevention. Aspirin and clopidogrel are antiplatelet agents, not anticoagulants, and are less effective in preventing thromboembolic events in atrial fibrillation.

Correct Answer: C

Rationale: The correct answer is C: Hyperglycemia. Corticosteroids can increase blood sugar levels by promoting gluconeogenesis and decreasing glucose uptake in cells. This leads to hyperglycemia. Choice A is incorrect because corticosteroids usually cause hyperglycemia, not hypoglycemia. Choice B is incorrect as corticosteroids typically increase appetite, not decrease it. Choice D is incorrect because weight gain, not weight loss, is a common side effect of corticosteroid use.

Correct Answer: A

Rationale: The correct answer is A: Increasing serotonin levels in the brain by inhibiting its reuptake. Sertraline is a selective serotonin reuptake inhibitor (SSRI), which means it inhibits the reuptake of serotonin in the brain, leading to increased levels of serotonin available for neurotransmission. This helps alleviate symptoms of depression by enhancing serotonin signaling. Choices B, C, and D are incorrect because sertraline specifically targets serotonin reuptake, not norepinephrine, dopamine, monoamine oxidase, or acetylcholine.

Correct Answer: B

Rationale: The correct answer is B: Inhibiting osteoclast-mediated bone resorption. Zoledronic acid is a bisphosphonate that works by inhibiting osteoclast activity, thereby reducing bone resorption. This helps in increasing bone density and strength in conditions like osteoporosis. Other choices are incorrect because zoledronic acid does not directly affect bone formation by osteoblasts (choice A), calcium absorption from the gut (choice C), or the secretion of parathyroid hormone (choice D).