Repetitive stimulation of olfactory receptor cells in female silkmoths Bombyx mori L

The pheromone-sensitive receptor cells of male moth antennae are capable of detecting the rapid changes in stimulus intensity encountered in natural pheromone odour plumes. We investigated temporal response characteristics of the two receptor cell types of the sensillum trichodeum of female Bombyx mori, which are most sensitive to benzoic acid and 2,6-dimethyl-5-heptene-2-ol (DMH), respectively. The cells were repetitively stimulated with 50-ms pulses of benzoic acid and (+/-)-linalool, an effective mimic of DMH, at various pulse rates and different stimulus intensities. By recording receptor potentials and nerve impulses we demonstrated that both receptor cell types were able to follow stimulus pulses at least up to eight pulses per sec, with a more pronounced modulation of the responses in the DMH cell. The resolution capability of the two cell types showed little dependence on stimulus intensity. In their ability to resolve pulsed odour stimuli, the receptor cells for benzoic acid and DMH were as good as pheromone receptor cells.