Indicate the side effect of Theophylline:

Correct Answer: B

Rationale: The correct answer is B: Increased myocardial demands for oxygen. Theophylline is a bronchodilator that works by relaxing the smooth muscles in the airways. This relaxation can lead to increased heart rate and contractility, causing the heart to work harder and increasing its demand for oxygen. Bradycardia (choice A) is not a common side effect of Theophylline. Depression of the respiratory center (choice C) is also not a typical side effect, as Theophylline is a respiratory stimulant. Elevation of arterial blood pressure (choice D) is not directly caused by Theophylline but can occur as a secondary effect due to increased heart rate and contractility.

Correct Answer: A

Rationale: Correct Answer: A Rationale: A: ACE inhibitors directly inhibit the conversion of angiotensin I to angiotensin II, not angiotensinogen to angiotensin I. B: Enalapril is indeed a prodrug that is converted to an active metabolite. C: ACE inhibitors do reduce the secretion of aldosterone. D: ACE inhibitors can lead to hyperkalemia when combined with a potassium-sparing diuretic due to decreased aldosterone levels.

Correct Answer: D

Rationale: Step-by-step rationale for D (Minoxidil) as the correct answer: 1. Minoxidil is a vasodilator used for hypertension. 2. It acts by opening potassium channels in vascular smooth muscle cells. 3. Opening potassium channels leads to hyperpolarization, causing relaxation. 4. This relaxation reduces peripheral vascular resistance, decreasing blood pressure. Summary: A (Dipyridamole) is a platelet inhibitor, not a potassium channel opener. B (Validol) is a mild cardiac sedative. C (Atenolol) is a beta-blocker. The correct answer is D (Minoxidil) because it directly acts on potassium channels to induce vasodilation.

Correct Answer: A

Rationale: Nicergoline is the correct answer as it is a derivative of Ergot. Ergot alkaloids are compounds derived from the ergot fungus and Nicergoline falls under this category. Warfarin is a blood thinner, Cinnarizine is a calcium channel blocker, and Vinpocetine is a nootropic drug. These drugs are not derivatives of Ergot, making them incorrect choices.

Correct Answer: A

Rationale: The correct answer is A because glucagon is a hormone released by the pancreas in response to low blood sugar levels. Glucagon stimulates gluconeogenesis in the liver, which is the process of synthesizing glucose from non-carbohydrate sources like amino acids and glycerol. This helps increase blood glucose levels. Choice B is incorrect because glucagon actually inhibits the secretion of insulin by beta cells. Choice C is incorrect because glucagon does not inhibit glucose utilization by skeletal muscle; instead, it promotes the breakdown of glycogen to release glucose. Choice D is incorrect because glucagon does not inhibit the uptake of amino acids by cells; it actually promotes the breakdown of stored energy sources like glycogen and fat.