[The pathophysiology of cerebral circulation].

Area of Science:

• Neuroscience
• Cerebrovascular Medicine
• Physiology

Context:

• Cerebral circulation deficits significantly impact central nervous system (CNS) function and morphology.
• Generalized cerebral ischemia triggers a predictable sequence of electrical and metabolic disturbances.
• Experimental models illustrate these functional and morphological changes.

Purpose:

• To review the characteristic functional and morphological disturbances in the CNS caused by local and generalized decreases in cerebral circulation.
• To characterize the typical signs of various types of hypoxia (oligemic, anoxic, hypoxic, anemic, venous, histotoxic).
• To discuss ionic fluxes, particularly cations, in energy-deficient brain tissue and their role in regulating cerebral artery wall tension.
• To describe blood flow redistribution following occlusion of brain-supplying arteries.

Summary:

• Generalized cerebral ischemia and severe hypoxia with cerebral artery occlusion induce similar changes in energy metabolism and electrical activity.
• The review outlines the distinct features of different hypoxic conditions.
• Ionic fluxes across neuronal and vascular smooth muscle cell membranes are crucial in energy-deficient brain tissue.
• Interactions of ions regulating vessel wall tension and post-occlusion blood flow redistribution are examined.

Impact:

• Provides a comprehensive overview of the physiological responses to cerebral ischemia and hypoxia.
• Highlights the critical role of ionic fluxes in the pathophysiology of brain energy deficits.
• Offers insights into cerebrovascular regulation and blood flow dynamics in response to arterial occlusion.