| First Author | Alarcon-Martinez L | Year | 2018 |
| Journal | Elife | Volume | 7 |
| PubMed ID | 29561727 | Mgi Jnum | J:316370 |
| Mgi Id | MGI:6823111 | Doi | 10.7554/eLife.34861 |
| Citation | Alarcon-Martinez L, et al. (2018) Capillary pericytes express alpha-smooth muscle actin, which requires prevention of filamentous-actin depolymerization for detection. Elife 7:e34861 |
| abstractText | Recent evidence suggests that capillary pericytes are contractile and play a crucial role in the regulation of microcirculation. However, failure to detect components of the contractile apparatus in capillary pericytes, most notably alpha-smooth muscle actin (alpha-SMA), has questioned these findings. Using strategies that allow rapid filamentous-actin (F-actin) fixation (i.e. snap freeze fixation with methanol at -20 degrees C) or prevent F-actin depolymerization (i.e. with F-actin stabilizing agents), we demonstrate that pericytes on mouse retinal capillaries, including those in intermediate and deeper plexus, express alpha-SMA. Junctional pericytes were more frequently alpha-SMA-positive relative to pericytes on linear capillary segments. Intravitreal administration of short interfering RNA (alpha-SMA-siRNA) suppressed alpha-SMA expression preferentially in high order branch capillary pericytes, confirming the existence of a smaller pool of alpha-SMA in distal capillary pericytes that is quickly lost by depolymerization. We conclude that capillary pericytes do express alpha-SMA, which rapidly depolymerizes during tissue fixation thus evading detection by immunolabeling. |
