Why does increased endothelin-1 secretion lead to hypertension rather than hypotension in a patient?

💡 Explanation

Endothelin-1 causes hypertension because it is a potent vasoconstrictor, leading to increased peripheral resistance and therefore higher blood pressure. Rather than lowering pressure like ANP or reducing activity of the renin-angiotensin system, endothelin-1 increases vessel resistance.

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