cells Article Function and Biomarkers of the Blood-Brain Barrier in a Neonatal Germinal Matrix Haemorrhage Model Erik Axel Andersson 1 , Eridan Rocha-Ferreira 2 , Henrik Hagberg 2, Carina Mallard 1 and Carl Joakim Ek 1,* 1 Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Medicinaregatan 11, 413 90 Gothenburg, Sweden;
[email protected] (E.A.A.);
[email protected] (C.M.) 2 Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, 413 90 Gothenburg, Sweden;
[email protected] (E.R.-F.);
[email protected] (H.H.) * Correspondence:
[email protected] Abstract: Germinal matrix haemorrhage (GMH), caused by rupturing blood vessels in the germinal matrix, is a prevalent driver of preterm brain injuries and death. Our group recently developed a model simulating GMH using intrastriatal injections of collagenase in 5-day-old rats, which corresponds to the brain development of human preterm infants. This study aimed to define changes to the blood-brain barrier (BBB) and to evaluate BBB proteins as biomarkers in this GMH model. Regional BBB functions were investigated using blood to brain 14C-sucrose uptake as well as using biotinylated BBB tracers. Blood plasma and cerebrospinal fluids were collected at various times after GMH and analysed with ELISA for OCLN and CLDN5. The immunoreactivity of BBB proteins was assessed in brain sections. Tracer experiments showed that GMH produced a defined region surrounding the hematoma where many vessels lost their integrity. This region expanded for at least 6 h following GMH, thereafter resolution of both hematoma and re-establishment of BBB Citation: Andersson, E.A.; Rocha- Ferreira, E.; Hagberg, H.; Mallard, C.; function occurred.