Activity‐dependent ATP release from neurons and astrocytes

Abstract

Adenosine triphosphate (ATP) is released as an autocrine and paracrine extracellular signal that can activate a diverse set of purinergic receptors, including P2X ion channels and P2Y G‐protein coupled receptors. For example, during synaptic transmission both neurons and astrocytes can release ATP in an activity‐dependent manner, but it remains a challenge to directly visualize these extracellular ATP dynamics. We are therefore developing genetically‐encoded fluorescent sensors to quantify changes in the levels of extracellular ATP, and we have now engineered a second‐generation sensor with higher affinity for ATP. Using co‐cultures of primary mouse neurons and astrocytes, we demonstrate that our new sensor can be used to detect neuron‐activity dependent release of ATP. We also use our new sensor to detect ATP release during in vitro injury models including hypoosmotic shock and chemical ischemia. Importantly, we also demonstrate that dual‐sensor imaging experiments can be used to correlate changes in extracellular ATP with changes in intracellular signaling, such as via calcium (Ca2+) and cyclic adenosine monophosphate (cAMP) dynamics. Our results show that our sensor will be an effective tool for studying purinergic signaling in real‐time.Support or Funding InformationNIH/NINDS R21 NS092010This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.