We examined the mechanism of the neutrophil (PMN)-dependent increase in pulmonary vascular permeability to protein after thrombin-induced pulmonary microembolism. Humoral factors that activate PMNs after thrombin-induced pulmonary microembolism were characterized in pulmonary lymph obtained from unanesthetized sheep challenged with intravenous infusion of alpha-thrombin. Time-dependent increase...

Tissue-type plasminogen activator (t-PA) can modulate permeability of the neurovascular unit and exacerbate injury in ischemic stroke. We examined the effects of t-PA using in vitro models of the blood-brain barrier. t-PA caused a concentration-dependent increase in permeability. This effect was dependent on plasmin formation and potentiated in the presence of plasminogen. An inactive t-PA vari...

Aquaporin 4 (AQP4) is the predominant water channel in the mammalian brain and is mainly expressed in the perivascular glial endfeet at the brain-blood interface. AQP4 has been described as an important entry and exit site for water during formation of brain edema and regulation of AQP4 is therefore of therapeutic interest. Phosphorylation of some aquaporins has been proposed to regulate their ...

The recent development of a technique for quantitative measurement of conjunctival microvascular permeability has permitted detailed pharmacological evaluation of H1- and H2-receptor involvement in histamine-induced increases in conjunctival microvascular permeability and the role of histamine in microvascular permeability changes associated with immediate hypersensitivity responses in the conj...

The hamster cheek pouch preparation was used to assess microvascular permselectivity responses to three vasodilating agents: bradykinin, adenosine, and papaverine. Fluorescein isothiocyanate-dextran 150 was injected intravenously as a macromolecular tracer. To quantify changes in permeability, we calculated fluorochrome clearance values from the ratio of suffusate to plasma fluorescein isothioc...

Vascular permeability is frequently associated with inflammation and is triggered by a cohort of secreted permeability factors such as vascular endothelial growth factor (VEGF). Here, we show that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and is independent of VEGF. Global or endothelial-specific deletion of PR blocks...

BACKGROUND Lipopolysaccharide (LPS) was shown to induce an increase in caveolin-1 (Cav-1) expression in endothelial cells; however, the mechanisms regarding this response and the consequences on caveolae-mediated transcellular transport have not been completely investigated. This study aims to investigate the role of LPS-induced Cav-1 phosphorylation in pulmonary microvascular permeability in p...

Solid-extracellular fluid interaction is believed to play an important role in the strain-rate dependent mechanical behaviors of shoulder articular cartilages. It is believed that the kangaroo shoulder joint is anatomically and biomechanically similar to human shoulder joint and it is easy to get in Australia. Therefore, the kangaroo humeral head cartilage was used as the suitable tissue for th...

Novel biodegradable and pH-sensitive polymersomes prepared from poly(ethylene glycol) and poly(d,l-lactide) grafted poly(beta-amino ester) exhibit pH dependent permeability on hydrophilic solutes of which permeability is determined by the packing state of poly(d,l-lactide) membrane followed by ionization of poly(beta-amino ester) inducing loosely packed membrane formation from well-ordered pack...

Congenital haemolytic anaemia in a 14 year old girl was caused by increased red cell membrane cation permeability. Potassium permeability was unusually sensitive to hydrostatic pressure and treatment with N-ethylmaleimide, factors which activate a specific chloride dependent potassium channel in cell membranes.