What is the physiological significance of 'Intrinsic Sympathomimetic Activity' (ISA) in beta-blockers like Pindolol?
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Correct answer: They act as partial agonists, causing less resting bradycardia than pure antagonists
Beta-blockers with ISA slightly stimulate the receptor while simultaneously blocking the binding of more potent endogenous catecholamines. This results in a lower risk of extreme bradycardia at rest compared to drugs like propranolol.
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