In 1972, a British pharmacologist named Geoffrey Burnstock published a paper proposing that ATP is released from nerve terminals and acts as a neurotransmitter. The scientific establishment's response was a dismissal. The objections were that as the universal energy currency of all living cells, ATP was too ubiquitous to serve as a signal among neurons––it was everywhere, inside everything. That skepticism delayed a medical revolution by two decades. Burnstock continued wor