This study investigated changes in vascular endothelial cell tight junction structure and the expression of the gene encoding connexin 40 (Cx40) at the early pneumonedema stage of hyperoxia‑induced bronchopulmonary dysplasia (BPD) in a newborn rat model. A total of 96 newborn rats were randomly assigned to one of the following two groups, the hyperoxia group (n=48) and the control group (n=48)....

Sepsis is a deadly disease characterized by the inability to regulate the inflammatory-coagulation response in which the endothelium plays a key role. The cause of this perturbation remains poorly understood and has hampered the development of effective therapeutics. Matrix metalloproteases (MMPs) are involved in the host response to pathogens, but can also cause uncontrolled tissue damage and ...

BACKGROUND Increased pulmonary vascular permeability is a hallmark of acute lung injury (ALI). Gap junction channels (GJCs) connect adjacent cells and facilitate ion exchange. It remained unclear whether GJCs modulate pulmonary permeability in ALI through intracellular calcium. OBJECTIVES This study aimed to verify if GJCs in pulmonary microvessel endothelial cells (PMVECs) modulate pulmonary...

One of the most widely recognized mechanisms to initiate an inflammatory response is calcium entry into endothelial cells.1–3 Recent investigations have demonstrated that there are multiple mechanisms which determine calcium flux into endothelial cells (including ligand gated calcium channels, store operated calcium channels and mechanosensitive channels), and that these different mechanisms ar...

Fluid transport across epithelial and endothelial barriers occurs in the neonatal and adult lungs. Biophysical measurements in the intact lung and cell isolates have indicated that osmotic water permeability is exceptionally high across alveolar epithelia and endothelia and moderately high across airway epithelia. This review is focused on the role of membrane water-transporting proteins, the a...

INCREASED ENDOTHELIAL PERMEABILITY of pulmonary microvessels is the major contributor of acute lung injury, sepsis, and acute respiratory distress syndrome (2, 7). Studies have established that change in cell shape resulting in concurrent formation of gaps between endothelial cells is a primary determinant of increase in endothelial permeability (2, 7). Proinflammatory mediators (such as thromb...

Recent permeability studies comparing endothelial cell phenotypes derived from alveolar and extra-alveolar vessels have significant implications for interpreting the mechanisms of fluid homeostasis in the intact lung. These studies indicate that confluent monolayers of rat pulmonary microvascular endothelial cells had a hydraulic conductance (L(p)) that was only 5% and a transendothelial flux r...

Ischemia-reperfusion (I/R) lung injury is characterized by increased pulmonary endothelial permeability and edema, but the genetic basis for this injury is unknown. We utilized an in vivo mouse preparation of unilateral lung I/R to evaluate the genetic determinants of I/R lung injury. An index of pulmonary vascular protein permeability was measured by the ratio of left-to-right lung Evans blue ...

Thromboxane A2 (TXA2) is produced in the lungs of patients suffering from acute lung injury (ALI). We assessed its contribution in disease progression using three different ALI mouse models. The administration of hydrochloric acid (HCl) or oleic acid (OA)+ lipopolysaccharide (LPS) caused tissue edema and neutrophil infiltration with TXA2 production in the lungs of the experimental mice. The adm...

In this synopsis of a symposium at EB2007, we start with an overview of noise and impedance analyses that have been applied to various epithelial barriers. Noise analysis yields specific information about ion channels and their regulation in epithelial and endothelial barriers. Impedance analysis can yield information about apical and basolateral membrane conductances and paracellular conductan...