Action of adrenaline on which of the following receptor is not required in the treatment of analphylactic shock

**Core Concept**
Adrenaline (epinephrine) is a hormone and medication that plays a crucial role in the treatment of anaphylactic shock. It acts on various receptors to counteract the life-threatening symptoms of anaphylaxis. The correct understanding of adrenaline's action on different receptors is essential to manage anaphylactic shock effectively.

**Why the Correct Answer is Right**
Adrenaline acts on alpha-1 (α1) adrenergic receptors to cause vasoconstriction, which increases blood pressure. It also acts on beta-2 (β2) adrenergic receptors to cause bronchodilation, which improves respiratory function. Additionally, adrenaline acts on alpha-2 (α2) adrenergic receptors to inhibit the release of histamine from mast cells, which helps to reduce vascular permeability. The action of adrenaline on beta-1 (β1) adrenergic receptors is not required in the treatment of anaphylactic shock, as it primarily causes increased heart rate and contractility, which are not the primary concerns in anaphylaxis.

**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because alpha-1 (α1) adrenergic receptors are crucial for vasoconstriction in anaphylaxis.
**Option B:** Incorrect because beta-2 (β2) adrenergic receptors are essential for bronchodilation in anaphylaxis.
**Option C:** Incorrect because alpha-2 (α2) adrenergic receptors help to reduce histamine release from mast cells in anaphylaxis.

**Clinical Pearl / High-Yield Fact**
In the treatment of anaphylactic shock, adrenaline should be administered intramuscularly (IM) in a dose of 0.3-0.5 mg, repeated every 5-15 minutes as needed.

**Correct Answer:** D.