Stimulation intensity as critical determinant of presynaptic receptor effectiveness.

A number of reports in the literature suggest that there is an inverse correlation between the intensity of nerve activation and the effectiveness of presynaptic receptors that inhibit transmitter release. This common feature of many presynaptic inhibitory receptors may provide important insights into the mechanism by which transmitter release is controlled. Sue Duckles and Dénes Budai discuss the implications such a relationship between the pattern of nerve activation and effectiveness of presynaptic receptors has for understanding the physiological role of neuromodulators in general.