Muscles help us run, skip and jump at will, but are equally important in supporting processes that don’t involve any conscious decision, such as pumping blood around our body. Our blood vessel walls have smooth muscle cells that contract and relax to control blood pressure. To help us grow, develop and respond to injury, these muscle cells can also morph and move to affected regions. Unfortunately sometimes they get stuck inside blood vessels, blocking the flow of blood. Scientists are exploring calcium channels, special pores in the cell membrane, to try and determine why these changes happen. Calcium enters cells through these portals causing actin, a muscle cell protein, to contract. In a cell without channels (pictured, its nucleus shown in green), actin remains as long filaments (shown in red). If actin can’t flex, cells are unable to move and could obstruct vessels.
Written by Sai Pathmanathan
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