Differentiation of human germinal matrix vessels in the third trimester

• Published in: The FASEB journal 2007-04, Vol.21 (5), p.A230-A230
• Main Authors: Anstrom, John A., Thore, Clara R., Moody, Dixon M., Mott, Ryan T., Brown, William R.
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.21.5.A230-c

Neonates born prematurely are commonly afflicted by germinal matrix hemorrhage‐interventricular hemorrhage (GMH‐IVH). The incidence of GMH‐IVH decreases with increasing gestational age, which supports the concept that the declining incidence is related to structural development of germinal matrix (GM) vessels. In the current study, GM vessels were evaluated throughout the 24–34 week gestational interval to determine the development of two features: endothelial cell alkaline phosphatase (AP) expression and the development of tight junctions (TJ). AP activity was studied by histochemical staining of brain sections. At 24 weeks, AP expression was sporadic within the GM, whereas all afferent cortical vessels expressed AP. By 28 weeks, GM vessels uniformly expressed AP. Development of TJs in GM vessels was monitored by immunochemistry using antibodies specific for TJ proteins. At 24 weeks, cortical vessels displayed TJs that outlined the periphery of endothelial cells, whereas GM vessels were characterized by a staining pattern that included short, linear elements enhanced sporadically by bright spots. By 34 weeks GM vessels displayed TJ staining patterns resembling those observed in cortical vessels. The developmental timing of both AP and TJs support the hypothesis that GM endothelial cells are incompletely differentiated at 24 weeks gestation. Supported by NIH NS36780 to DMM.