Inverse agonist is

Correct Answer: C

Rationale: Inverse agonists bind to the same receptor as an agonist but produce the opposite effect. Beta carbolines act as inverse agonists by decreasing basal activity of GABA receptors. Buspirone is a partial agonist of serotonin receptors. Flumazenil is a benzodiazepine antagonist. Zolpidem is a positive allosteric modulator of GABA receptors.

Correct Answer: D

Rationale: The correct answer is D: Chills. The four classic signs of inflammation are warmth, redness, swelling, and pain. Chills are not a direct result of inflammation but rather a response to fever or infection. Warmth, redness, and swelling are caused by increased blood flow to the affected area, leading to dilation of blood vessels and leakage of fluid into the tissues. Chills typically occur as a response to a systemic infection and are not specific to inflammation at a localized site.

Correct Answer: D

Rationale: Platelet aggregation is a complex process involving various mediators. Prostaglandins and thromboxane are both derived from arachidonic acid and play crucial roles. Thromboxane promotes platelet aggregation by stimulating vasoconstriction and platelet activation. Prostaglandins also contribute to platelet aggregation by enhancing thromboxane synthesis and promoting platelet adhesion. Prostacyclin, on the other hand, inhibits platelet aggregation by inducing vasodilation and inhibiting platelet activation. Therefore, the correct answer is D, as both prostaglandins and thromboxane promote platelet aggregation. Choices A, B, and C are incorrect as they do not capture the dual role of prostaglandins and thromboxane in platelet aggregation.

Correct Answer: D

Rationale: Correct Answer: D - Vecuronium Rationale: Vecuronium is a non-depolarizing neuromuscular blocking agent that blocks the action of acetylcholine at the neuromuscular junction, preventing muscle contraction. It does not directly cause muscle contractions or twitching. Summary: A: Acetylcholine - Stimulates muscle contraction by binding to receptors at the neuromuscular junction. B: Strychnine - Enhances spinal reflexes leading to muscle twitches and spasms. C: Succinylcholine - Acts as a depolarizing neuromuscular blocker, leading to muscle contractions.

Correct Answer: B

Rationale: The correct answer is B: MAO inhibitors. Phenelzine and tranylcypromine are both monoamine oxidase inhibitors (MAOIs). MAOIs work by blocking the enzyme monoamine oxidase, which increases the levels of neurotransmitters such as serotonin, norepinephrine, and dopamine in the brain. This leads to an improvement in mood and alleviation of depressive symptoms. Tricyclic antidepressants (choice A) work by blocking the reuptake of neurotransmitters, 5-HT uptake inhibitors (choice C) specifically target serotonin reuptake, and atypical antidepressants (choice D) have various mechanisms of action different from MAOIs. Therefore, the correct choice is B as phenelzine and tranylcypromine are classified as MAO inhibitors.