Microscope Image Showing Astrocyte Diversity across the Mouse Brain (image) McGill University Health Centre Share Print E-Mail Caption Astrocytes are brain cells that interact intimately with neurons and their circuits to maintain proper conditions for nervous system function. Neurons release a protein called Sonic hedgehog (Shh) to determine the molecular and physiological properties of astrocytes throughout the brain. In the image, the Shh signaling pathway has been activated in a subset of astrocytes (red). These cells produce high levels of Kir4.1 (green), a potassium channel needed to maintain proper potassium levels and neuron activity. Credit Todd Farmer, McGill University Health Centre Usage Restrictions Credit Todd Farmer, McGill University Health Centre Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.