Calcineurin is part of a negative feedback loop in the InsP3/Ca2+ signalling pathway in blowfly salivary glands

- Hormone-induced Ca2+ signals were recorded in blowfly salivary glands.
- Inhibition of calcineurin causes an increase in hormone-induced Ca2+ responses.
- Inhibition of calcineurin causes an increase in InsP3-dependent Ca2+ release.
- Calcineurin provides a negative feedback on InsP3/Ca2+ signalling, counteracting the effect of PKA.