Photocaged Oxytocin and Vasopressin Probes to Decipher Neuropeptide Signalling With High Spatiotemporal Resolution

R). The coumarin cage proved the most effective, suppressing OT/VP bioactivity until rapid photouncaging enabled on-demand receptor activation. It excelled in cellular assays, primary rat hippocampal neurones, and ex vivo acute mouse brain slices, demonstrating broad applicability. It is biocompatible, readily incorporated into peptides, and compatible with various neuronal experimental setups. Photo-uncaging can be performed with inexpensive light-emitting diode (LED) setups, as well as with extreme precision via two-photon excitation, enabling investigations of neuropeptide signalling with high spatiotemporal resolution, offering new opportunities to investigate neuropeptide function in health and disease.