Pick out the right statement:

Correct Answer: C

Rationale: The correct answer is C. Microsomal oxidation involves the addition of functional groups, such as hydroxyl groups, to a drug molecule, increasing its polarity, ionization, and water solubility. This can enhance the drug's elimination from the body through renal excretion. Choice A is incorrect as microsomal oxidation does not always result in inactivation. Choice B is incorrect because microsomal oxidation can sometimes increase compound toxicity by producing reactive metabolites. Choice D is incorrect as microsomal oxidation typically increases water solubility, not lipid solubility, of a drug.

Correct Answer: A

Rationale: The correct answer is A because bupivacaine is known for its high cardiotoxicity compared to other local anesthetics. This is due to its ability to cause cardiac arrhythmias at lower doses. Choice B is correct as bupivacaine does have an amide linkage. Choice C is correct as it is a long-acting drug, providing prolonged anesthesia. Choice D is correct as an intravenous injection of bupivacaine can indeed lead to seizures due to its central nervous system toxicity.

Correct Answer: D

Rationale: Atropine is rarely used for peptic ulcer treatment due to its adverse effects, which include slow gastric emptying leading to prolonged exposure of the ulcer bed to acid, low efficiency requiring large doses, and other possible side effects. Therefore, the correct answer is D as it encompasses all the reasons why atropine is not commonly used for peptic ulcer treatment. Choices A, B, and C individually address specific drawbacks of atropine, but only D covers all the reasons comprehensively.

Correct Answer: B

Rationale: The correct answer is B: α2 receptor. Epinephrine binds to α2 receptors, leading to inhibition of adenylate cyclase activity, which decreases intracellular cAMP levels. α1 receptors are Gq-coupled and increase intracellular calcium levels. Beta1 receptors are also Gs-coupled, leading to increased cAMP levels. Beta2 receptors, like α2 receptors, are Gi-coupled and decrease cAMP levels. Therefore, the correct answer is B because epinephrine acts on α2 receptors to decrease cAMP levels.

Correct Answer: B

Rationale: The correct answer is B: Phenylephrine. Phenylephrine is an effective mydriatic because it acts on alpha-1 adrenergic receptors in the eye, causing pupillary dilation. Salmeterol (A) is a long-acting beta-2 agonist used for asthma, not mydriasis. Dobutamine (C) is a beta-1 agonist used for cardiac support. Norepinephrine (D) is a non-selective adrenergic agonist used for hypotension, not for mydriasis.