[The role of mechanical stresses in the formation and orientation of vessel-like structures in explants of clawed toad embryos].
The role of mechanical tensions in the formation of blood vessel-like tubes and lumens in embryonic Xenopus laevis mesenchyme was studied using ectomesoderm explanted from the area of ventral blood islands. The mechanical tensions in extracellular matrix of the explanted mesenchyme were caused by slightly squeezing the explants between two parallel coverslips. Long-term deformations (50 min and more) followed by incubation for 40 min resulted in the formation of vessel-like tubes and circular structures by mesenchymal cells oriented along the plane of stretching. The circular structures were similar to those formed by angioblasts during development of the blood vessel lumen. The comparison between long- and short-term (3 min) stretching experiments demonstrated that these effects represent the result of active cell reactions rather than of a rapid passive cellular response to stretching of the substrate. It is suggested that similar morphogenetic reactions take place during the vessel tube formation in the course of embryonic vasculogenesis.
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Fesenko
D000818:Animals; D001808:Blood Vessels / Q000196:embryology*; D046508:Culture Techniques; D008648:Mesoderm / Q000166:cytology; D009024:Morphogenesis; D013314:Stress, Mechanical; D013997:Time Factors; D014982:Xenopus laevis / Q000196:embryology*