Capillary structure

Capillaries are the smallest blood vessels in the body, forming networks (capillary beds) that connect arterioles and venules[1][7]. The capillary wall consists of a single layer of endothelial cells and a basement membrane, sometimes accompanied by pericytes[1][2]. There are three main types: - Continuous capillaries (no pores, found in muscle, skin, CNS; constituent of the blood-brain barrier)[2][4][5][7] - Fenestrated capillaries (small pores in the endothelial cells, found in kidneys, intestines, endocrine glands)[2][4][5][7] - Sinusoidal (discontinuous) capillaries (large gaps and incomplete basement membrane, found in liver, spleen, bone marrow)[2][4][5][7] Capillary structure allows for selective exchange of gases, nutrients, and waste between blood and tissues, driven by the specific permeability of each capillary type. Permeability can be highly regulated and varies among tissue types. Capillaries play essential roles in maintenance of tissue homeostasis, and dysfunction may contribute to disease states such as edema, ischemia, and septic shock[1][4]. In summary: "Capillary structure" is *not* a molecular target, but a descriptive term for the architecture of capillaries. All pharmacological or therapeutic targeting pertains to cellular or molecular components within the capillary (most commonly endothelial cells or associated proteins), not to the structure as a whole[1][7].

Other names

Blood capillarymicrovesselcapillary bed