Experience Mediated Development of the Visual Cortex Vascularization

The brain is highly vascularised, containing a very intricate network of capillaries (nearly

every brain cell is located within 20 μm of a capillary). The endothelial cells that form the
brain capillaries are sealed together by tight junctions, and have no fenestrations and very
low pinocytosis. This combination of features creates the BBB, which is both a physical and
enzymatic barrier.

Angiogenesis is one of the main adaptive mechanisms of brain microcirculation to changing
needs of the CNS, as happens in the development of the visual cortex under the influence of
visual activity, mainly during the critical period.

The nervous system needs a stable internal environment, which is created by the Blood
Brain Barrier (BBB). The BBB function is related to structural and functional features of the
vascular endothelium. Both the development of angioarchitecture and the functional
maturation of the BBB occur postnatally and are regulated by tissue microenvironment and
external environment. The development of the vascular tree, the acquisition of functional
competence by the BBB and the induction and modulation of neoangiogenesis are closely
dependent on the changes in metabolic demand induced by functional modifications
(increases or decreases of stimuli).

The vascular network plays a crucial role in development and function of the CNS. It adapts
to specific changes of metabolic demand and local flow modifications. However, if these
changes become permanent, the supply is ensured by neoangiogenesis. Angiogenic,
neurotrophic and neuroprotective factors participate in the development and maintenance
of vascular, astroglial and neuronal structures, suggesting that the neurogliovascular unit
preserves brain integrity. The improvement of the neurogliovascular unit by mechanisms
such as the direct administration or the indirect stimulation of secretion of angioglioneurins
could be an efficient strategy in brain diseases.

SOURCE: Enrike G. Argandoña, Harkaitz Bengoetxea, Naiara Ortuzar, Susana Bulnes, Irantzu Rico-Barrio and José Vicente Lafuente (2012). Experience Mediated Development of the Visual Cortex Vascularization, Visual Cortex – Current Status and Perspectives, Stephane Molotchnikoff and Jean Rouat (Ed.), ISBN: 978-953-51-0760-6, InTech

Available from: http://www.intechopen.com/books/visual-cortex-current-status-and-perspectives/experience-mediated-development-of-the-visual-cortex-vascularization


Leave a Reply

 

 

 

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>