The Vascular System of the Cerebral Cortex

ISBN-13: 9783540096528 / Angielski / Miękka / 1980 / 62 str.

Thomas Bar

Opis

A vascular system consists of a supplying arterial and a draining venous part which are connected by a terminal vascular network. The arterial segment can be characterized according to the structural features of the vessel wall. However, it is sometimes diffi- cult to distinguish the capillary from the postcapillary vessels on the basis of structural features alone. On the other hand, physiologic qualities such as permeability can hard- ly be associated with an equivalent histologic pattern of the vessel wall (lllig 1961; Rhodin 1967, 1968; Hauck 1971; Westergaard 1974). A defmition of a vascular seg- ment based on biologic significance should combine morphological and functional qualities of the vessel walls. During the ontogeny of the mammalian organism a variety of vascular patterns (e. g. , distribution of arteries and veins, arrangement of the capillaries) has been formed typical of each organ (Wolff et al. 1975; Baez 1977). The capillaries connect the feed- ing arterioles and the collecting venules in two different ways according to the branch- ing pattern of the terminal vessels (Hauck 1975, Wolff et al. , 1975). The arterioles and venules are directly connected by capillary segments. Consequently a terminal vessel called arteriovenous (a-v) capillary results, or a closely meshed capillary network is de- veloped which connects arterioles and venules by a variable number of small capillary branches arranged parallel to the preexisting a-v capillary.

Spis treści

1 Introduction.- 2 Material and Methods.- 3 Results.- 3.1 Extracerebral (Leptomeningeal) Vascularization.- 3.2 Intracerebral Vascularization.- 3.2.1 First Stage of Intracortical Vascularization.- 3.2.2 Second Stage of Intracortical Vascularization.- 3.2.3 Third Stage of Intracortical Vascularization.- 3.3 Morphometric Evaluation of Capillaries in Different Layers of the Cerebral Cortex by Automatic Image Analysis.- 3.4 Thickness of Cerebral Cortex During Postnatal Development.- 3.5 Morphometric Evaluation of Capillaries in Different Layers of the Cerebral Cortex by Automatic Image Analysis: Changes During Aging.- 3.6 Effects of Oxygen Deficiency on Intracortical Microvessels.- 3.6.1 Early Postnatal Period (Days 4-14).- 3.6.2 Days 14 to 54 After Birth.- 3.6 3 Days 30 to 70 After Birth.- 3.6.4 Days 80 to 120 After Birth.- 4 Discussion.- 4.1 Methodological Considerations.- 4.2 First Stage of Intracortical Vascularization and Architecture of Intracortical Vascular Trunks.- 4.3 Second Stage of Intracortical Vascularization.- 4.4 Third Stage of Intracortical Capillarization.- 4.5 Vascular Sprouting.- 4.6 Effects of Hypoxia Upon Postnatal Capillarization.- 4.7 Intracortical Capillaries During Aging.- 5 Summary.- References.