TY - JOUR TI - Capillary pericytes mediate coronary no-reflow after myocardial ischaemia AU - O'Farrell, Fergus M AU - Mastitskaya, Svetlana AU - Hammond-Haley, Matthew AU - Freitas, Felipe AU - Wah, Wen Rui AU - Attwell, David A2 - Watt, Fiona M VL - 6 PY - 2017 DA - 2017/11/09 SP - e29280 C1 - eLife 2017;6:e29280 DO - 10.7554/eLife.29280 UR - https://doi.org/10.7554/eLife.29280 AB - After cardiac ischaemia, a prolonged decrease of coronary microvascular perfusion often occurs even after flow is restored in an upstream artery. This 'no-reflow' phenomenon worsens patient prognosis. In the brain, after stroke, a similar post-ischaemic 'no-reflow' has been attributed to capillary constriction by contractile pericytes. We now show that occlusion of a rat coronary artery, followed by reperfusion, blocks 40% of cardiac capillaries and halves perfused blood volume within the affected region. Capillary blockages colocalised strongly with pericytes, where capillary diameter was reduced by 37%. The pericyte relaxant adenosine increased capillary diameter by 21% at pericyte somata, decreased capillary block by 25% and increased perfusion volume by 57%. Thus, cardiac pericytes constrict coronary capillaries and reduce microvascular blood flow after ischaemia, despite re-opening of the culprit artery. Cardiac pericytes are therefore a novel therapeutic target in ischaemic heart disease. KW - pericyte KW - capillary KW - heart KW - ischaemia JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -