. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 484 BASSOT ET AL. Post discharges occur with stronger stimuli consisting of brief bursts at high frequency. When such stimuli are repeated, successive post discharges get longer and brighter, involving more and more cumulative flashes. They often lead to the climax of an explosive response, in which flashes flicker at high frequency (10 per second) for several seconds. After such intense events, which remind the "frenzy" responses observed by Buck (1973) in Renilla, the system is nearly exhausted. Nevertheless, aft
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 484 BASSOT ET AL. Post discharges occur with stronger stimuli consisting of brief bursts at high frequency. When such stimuli are repeated, successive post discharges get longer and brighter, involving more and more cumulative flashes. They often lead to the climax of an explosive response, in which flashes flicker at high frequency (10 per second) for several seconds. After such intense events, which remind the "frenzy" responses observed by Buck (1973) in Renilla, the system is nearly exhausted. Nevertheless, after 5 to 20 min of recovery, the system is again responsive. The effectiveness of electrical stimulation has proven to be highly variable in different individuals. This is probably due to the fragility of the epithelium which, if damaged by the electrodes, can be excited only by increased stimulation. An epithelial potential is associated with each single flash as well as with each peak of a multiple response (Fig. 10). These pulses remain constant in shape and amplitude regardless of the brightness of the associated flash. Response latencies vary depending on the placement of the electrodes. Initially, at least three consecutive epithelial pulses are required to elicit the first component of the luminous response (Fig. 10). Thereafter, one to one responses occur when the stimulating shocks, and thus the epithelial pulses, are. FIGURE 10. Induction of luminescence. On left, A is a simultaneous record of luminescence (upper line), involution (actographic record, next below) and epithelial impulses (three lower records, successive sweeps about 4 sec apart). Single epithelial impulses produced perceptible degrees of involution, but no flash occurred until three epithelial pulses were evoked. Scale is 50 msec. On right, in B, a series of shocks evoked a corresponding series of epithelial pulses (lower trace). After the third one luminescence was evoked; each sub- sequent spike was a
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
