Coronary microcirculation: physiology and pharmacology

Area of Science:

• Cardiovascular Physiology
• Microcirculation Research
• Vascular Biology

Background:

• Coronary microvessels are crucial for myocardial oxygen and nutrient delivery.
• Their regulation involves intrinsic vascular controls, metabolic factors, and neurohumoral mediators.
• Understanding microvascular function is vital for cardiac health and disease pathophysiology.

Purpose of the Study:

• To review the endogenous regulatory systems of coronary circulation from a microvascular perspective.
• To explore the pharmacological responses of coronary microvessels.
• To highlight the importance of microvascular heterogeneity and permeability in myocardial perfusion and edema.

Main Methods:

• In vitro analysis of myogenic and flow-induced intrinsic vascular controls.
• In vivo studies of coronary microvascular responses during metabolic stimulation, autoregulation, and reactive hyperemia.
• Examination of neurohumoral mediator effects and size-dependent microvascular heterogeneity.

Main Results:

• Coronary microvascular control is mediated by a complex interplay of metabolic factors, intrinsic mechanisms, and neurohumoral signals.
• ATP-sensitive K(+) channels play a significant role in metabolic control.
• Size-dependent heterogeneity in microvascular responses is essential for optimal myocardial perfusion.

Conclusions:

• Optimal myocardial perfusion relies on the orchestrated, synergistic, and competitive interactions within the coronary microvasculature.
• Regulation of coronary microvascular permeability is critical for nutrient supply and preventing edema.
• Studying drug responses and disease-related impairments in coronary microvessels informs therapeutic strategies for microvascular dysfunction.