Both the older (tricyclic) antidepressants and the newer ones (e.g. fluoxetine) relieve signs and symptoms of depression mainly by doing which one of the following things?

Correct Answer: C

Rationale: TCAs (e.g., imipramine) and SSRIs (e.g., fluoxetine) (choice C) block reuptake of serotonin and/or norepinephrine, increasing synaptic levels to treat depression. Blocking receptors (choice A, B) or stimulating serotonin (choice D) aren't primary mechanisms. Reuptake inhibition is their shared action.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: A

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: B

Rationale: Acarbose (choice B) inhibits α-glucosidase, an enzyme in the small intestine that breaks down complex carbohydrates into glucose, delaying absorption and reducing postprandial glucose spikes in type 2 diabetes. Phosphodiesterase (choice A) is targeted by drugs like sildenafil, unrelated to glucose metabolism. Cyclo-oxygenase (choice C), inhibited by NSAIDs, affects prostaglandin synthesis, not carbohydrates. Cholinesterase (choice D), blocked by anticholinesterases, impacts acetylcholine, not glucose. α-glucosidase inhibition is Acarbose's specific action, making it effective for glycemic control without systemic insulin effects. This mechanism highlights its role in dietary glucose management, distinguishing it from other antidiabetic drugs and aiding in patient education about its GI side effects like flatulence.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.