Euler-Liljestrand mechanism

The Euler-Liljestrand mechanism describes the connection between ventilation and blood circulation(perfusion) of the lung. If the ventilation in a part of the lung decreases, this leads to local hypoxiaand to vasoconstriction in that part. This so-called shuntis an adaptive mechanismo that is beneficial, because it causes bloodto pass the lung without being oxygenated. The mechanism was discovered by two Swedishpharmacologists, Ulf von Euler(1905-1981) and Göran Liljestrandat the Department of Pharmacology of Karolinska Institutein Stockholm.

The molecularmechanism seems to be mediated by oxygen-sensitive potassiumion channelsin the cell membraneof pulmonary smooth muscle. With a low partial pressure of oxygen, these channels are blocked, leading to the depolarization of the cell membrane. Calciumchannels are activated and causes the influx of Ca2+ ions over the membrane and to the release of calcium from the endoplasmic reticulum. The rise of the calcium concentration causes the contraction of the smooth muscle fibers and the resulting vasoconstriction.

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It uses material from the http://en.wikipedia.org/wiki/Euler-Liljestrand+mechanism Wikipedia article Euler-Liljestrand mechanism.