Drugs that Regulate Vascular Tone

Vascular tone is another key determinant of tissue perfusion. Vascular smooth muscle cells are the functional regulatory units that integrate a variety of signals initiated by (1) local factors (e.g., H⁺, CO₂, stretch), (2) endothelium-derived signaling molecules (e.g., nitric oxide, prostacyclin), (3) neurotransmitters (e.g., epinephrine), and (4) hormones (e.g., vasopressin) to optimize vascular tone.⁶ Ultimately, vascular smooth muscle tone is determined by the intracellular Ca²⁺ ion concentration.

Drugs in the top 300 that regulate vascular tone (Table 3) include (1) Ca²⁺ channel blockers, (2) β1-adrenoceptor antagonists, (3) α1-adrenoceptor antagonists, (4) α2-adrenoceptor agonists, (5) K⁺ channel openers, (6) nitric oxide donors, and (7) late sodium current blockers.^2,6,7,10,11 These drug categories are intended for the management of systemic and pulmonary hypertension, ischemic heart disease (i.e., chronic coronary artery disease and acute coronary syndromes), and congestive heart failure^6,7