Vascular permeability

Differences in vascular permeability between normal tissue and a tumor

Vascular permeability, often in the form of capillary permeability or microvascular permeability, characterizes the capacity of a blood vessel wall to allow for the flow of small molecules (drugs, nutrients, water, ions) or even whole cells (lymphocytes on their way to the site of inflammation) in and out of the vessel. Blood vessel walls are lined by a single layer of endothelial cells. The gaps between endothelial cells (cell junctions) are strictly regulated depending on the type and physiological state of the tissue.[1][2][3][4]

There are several techniques to measure vascular permeability to certain molecules. For instance, the cannulation of a single microvessel with a micropipette, the microvessel is perfused with a certain pressure, occluded downstream and then the velocity of some cells will be related to the permeability.[5][6] Another technique uses multiphoton fluorescence intravital microscopy through which the flow is related to fluorescence intensity and the permeability is estimated from the Patlak transformation. [7]

An example of increased vascular permeability is in the initial lesion of periodontal disease, in which the gingival plexus becomes engorged and dilated, allowing large numbers of neutrophils to extravasate and appear within the junctional epithelium and underlying connective tissue.[8]

  1. ^ Azzi, Sandy; Hebda, Jagoda K.; Gavard, Julie (2013). "Vascular Permeability and Drug Delivery in Cancers". Frontiers in Oncology. 3: 211. doi:10.3389/fonc.2013.00211. ISSN 2234-943X. PMC 3744053. PMID 23967403.
  2. ^ Park-Windhol, Cindy; D'Amore, Patricia A. (2016-05-23). "Disorders of Vascular Permeability". Annual Review of Pathology: Mechanisms of Disease. 11 (1): 251–281. doi:10.1146/annurev-pathol-012615-044506. ISSN 1553-4006. PMC 8462517. PMID 26907525.
  3. ^ Komarova, Yulia; Malik, Asrar B. (2010-03-17). "Regulation of Endothelial Permeability via Paracellular and Transcellular Transport Pathways". Annual Review of Physiology. 72 (1): 463–493. doi:10.1146/annurev-physiol-021909-135833. ISSN 0066-4278.
  4. ^ Park, Ki-Sook; Schecterson, Leslayann; Gumbiner, Barry M. (2021-04-01). "Enhanced endothelial barrier function by monoclonal antibody activation of vascular endothelial cadherin". American Journal of Physiology. Heart and Circulatory Physiology. 320 (4): H1403–H1410. doi:10.1152/ajpheart.00002.2021. ISSN 0363-6135. PMC 8260392. PMID 33577432.
  5. ^ Michel, C. C., Mason, J. C., Curry, F. E. & Tooke, J. E. Development of Landis Technique for Measuring Filtration Coefficient of Individual Capillaries in Frog Mesentery. Q J Exp Physiol Cms 59, 283-309 (1974).
  6. ^ Bates, D. O. & Harper, S. J. Regulation of vascular permeability by vascular endothelial growth factors. Vascul Pharmacol 39, 225-237 (2002)
  7. ^ Patlak, C. S., Blasberg, R. G. & Fenstermacher, J. D. Graphical evaluation of blood-to-brain transfer constants from multiple-time uptake data. J Cereb Blood Flow Metab 3, 1-7 (1983).
  8. ^ Page, RC; Schroeder, HE. "Pathogenesis of Inflammatory Periodontal Disease: A Summary of Current Work." Lab Invest 1976;34(3):235-249