PKC-mediated inhibitory feedback of the cholecystokinin 1 receptor controls the shape of oscillatory Ca²⁺ signals.

Translation of extracellular hormonal input into cellular responses is often mediated by repetitive increases in cytosolic free Ca(2+) concentration ([Ca(2+) ]c ). Amplitude, duration and frequency of these so-called [Ca(2+) ]c oscillations then carry information about the nature and concentration of the extracellular signalling molecule. At present, there are different hypotheses concerning the induction and control of these oscillations.