Balance between vasoconstriction and enhanced oxygen delivery

Oxygen deficient α-Fe2O3 photoelectrodes: a balance between enhanced electrical properties and trap-mediated losses.

Intrinsic doping of hematite through the inclusion of oxygen vacancies (VO) is being increasingly explored as a simple, low temperature route to preparing active water splitting α-Fe2O3-x photoelectrodes. Whilst it is widely accepted that the introduction of VO leads to improved conductivities, little else is verified regarding the actual mechanism of enhancement. Here we employ transient absor...

Myoglobin-enhanced oxygen delivery to isolated cardiac mitochondria.

The heart, red skeletal muscles and the nitrogen-fixing legume root nodule function in steady states of high oxygen influx, partial oxygenation of cytoplasmic myoglobin or leghemoglobin and correspondingly low oxygen partial pressure. Here, we ask: what conditions are required at the surface of actively respiring, state III, tightly coupled mitochondria to enhance oxygen flow to cytochrome oxid...

Oxygen sensors in hypoxic pulmonary vasoconstriction.

Hypoxic pulmonary vasoconstriction (HPV) is an essential mechanism adapting lung perfusion to regional ventilation. Perturbations to HPV, such as those occurring in pneumonia, acute respiratory distress syndrome and liver failure, can result in arterial hypoxemia. Under conditions of general hypoxia, HPV increases pulmonary vascular resistance and thus causes acute pulmonary hypertension. Despi...

The pulmonary physician and critical care. 6. Oxygen transport: the relation between oxygen delivery and consumption.

Enhanced hypoxic pulmonary vasoconstriction in hypertension.

In this study, we tested the hypothesis that hypoxic pulmonary vasoconstriction may be enhanced in systemic hypertension. The hypothesis took origin from the following two considerations: alveolar hypoxia constricts the pulmonary vessels by enhancing the Ca2+ penetration across sarcolemma of the smooth muscle cells and systemic high blood pressure is associated with an elevation of tone and rea...