All of the following statements concerning angiotensin converting enzyme (ACE) inhibitors are true EXCEPT:

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: 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.

Correct Answer: A

Rationale: Prednisolone is the correct answer because it is a short- to medium-acting glucocorticoid, with a duration of action of about 12-36 hours. Dexamethasone is a long-acting glucocorticoid, with a duration of action of 36-72 hours. Triamcinolone is also a long-acting glucocorticoid with a duration of action of 12-36 hours. Therefore, choices B and C are incorrect. Choice D is incorrect because not all of the options are short- to medium-acting drugs.

Correct Answer: B

Rationale: The correct answer is B: Piperidines; i.e. Loratadine, Fexofenadine. Second-generation antihistamines like Loratadine and Fexofenadine belong to the piperidine category. Second-generation antihistamines are preferred over first-generation due to their lower sedative effects and longer duration of action. Alkylamines (A), Ethylenediamines (C), and Phenothiazines (D) are not classified as second-generation antihistamines and are associated with more sedation and anticholinergic side effects.