PHYSIOLOGY
MUSCLE RECEPTORS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Alpha 1 receptor
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Alpha 2 receptor
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Beta 1 receptor
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Beta 2 receptor
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Detailed explanation-1: -Pseudoephedrine and phenylephrine are Alpha-1 agonists. Mechanism of Action: Alpha-1 agonists stimulate alpha receptors in the respiratory tract, causing constriction of blood vessels and shrinkage of swollen nasal mucous membranes, thus increasing airway patency and reducing nasal congestion.
Detailed explanation-2: -The mechanism by which decongestants produce their action is activation of postjunctional a-adrenergic receptors found on precapillary and postcapillary blood vessels of the nasal mucosa.
Detailed explanation-3: -Phenylephrine is an alpha1 agonist with very little beta effect. Its major action is systemic and pulmonary arterial vasoconstriction, increasing SVR and systemic arterial pressure (systolic, diastolic, and mean). Reflex bradycardia can occur.