Which of the following antianginal agents refers to reflex coronary dilators:

Correct Answer: B

Rationale: Step-by-step rationale for why choice B (Validol) is the correct answer: 1. Validol contains menthol, which acts as a reflex coronary dilator. 2. Menthol stimulates cold receptors in the oral cavity, leading to vasodilation. 3. Vasodilation in the coronary arteries increases blood flow to the heart. 4. This helps relieve angina symptoms by improving blood supply to the heart muscle. Summary: - A: Dipyridamole is a vasodilator but acts through adenosine receptor stimulation, not reflex coronary dilation. - C: Atenolol is a beta-blocker that reduces heart rate and contractility but does not cause reflex coronary dilation. - D: Alinidine is a central alpha-2 adrenoceptor agonist, which reduces sympathetic outflow but does not directly cause reflex coronary dilation.

Correct Answer: B

Rationale: The correct answer is B because pancreatic β-cells secrete insulin, C-peptide, proinsulin, and islet amyloid polypeptide (IAPP). Insulin regulates blood sugar levels, C-peptide is a byproduct of insulin synthesis, proinsulin is the precursor of insulin, and IAPP helps in glucose metabolism. Choice A is incorrect as glucagon is secreted by α-cells, not β-cells, and proglucagon is not a primary secretory product of β-cells. Choice C is incorrect as somatostatin is mainly secreted by δ-cells in the pancreas, not β-cells. Choice D is incorrect as pancreatic polypeptide (PP) is secreted by PP-cells, a separate cell type in the pancreas, not by β-cells.

Correct Answer: C

Rationale: The correct answer is C because the chronic, proliferative phase of inflammation is characterized by tissue degeneration and fibrosis occurrence. During this phase, there is an attempt by the body to repair the damaged tissue by forming new connective tissue and blood vessels. A is incorrect because local vasodilatation and increased capillary permeability are characteristics of the acute phase of inflammation, not the chronic, proliferative phase. B is incorrect because the infiltration of leucocytes and phagocytic cells is typically seen in the acute phase of inflammation, not the chronic, proliferative phase. Therefore, the correct answer is C as it accurately reflects the characteristics of the chronic, proliferative phase of inflammation.

Correct Answer: A

Rationale: The correct answer is A, Piperidines like Loratadine and Fexofenadine are noted for their non-sedating effects due to their low penetration of the blood-brain barrier. This is because they have a low affinity for the central nervous system H1 receptors. In contrast, choices B, C, and D contain antihistamines that are known for their sedative effects due to their high penetration of the blood-brain barrier and high affinity for central nervous system H1 receptors. Therefore, Piperidines are the exception among the listed categories in not causing sedation.

Correct Answer: B

Rationale: The correct answer is B: Vitamin A. Vitamin A can be synthesized from a dietary precursor beta-carotene, which is found in various fruits and vegetables. The body converts beta-carotene into active Vitamin A as needed. Vitamin C (A) cannot be synthesized from a dietary precursor and must be obtained directly from the diet. Vitamin B1 (C) and Vitamin B6 (D) are water-soluble vitamins that cannot be synthesized from dietary precursors.