[Analysis of the mechanism of perception of temperature stimuli by the ampullae of Lorenzini of Black Sea skates]

Abstract

The single nerve fibre responses of the Lorenzini ampulla to thermal stimulation were studied in the Black Sea skates, Trygon pastinaca, and Raja clavata. Cooling of sea water applied to the ampulla capsule or to the skin overlying the sensory organ increased firing rate wheras warming led to transient decrease in frequency. The thermal sensitivity or receptors was found to depend on threshold to electric current. Static discharge rate of the receptors has positive or negative temperature coefficient according to the temperature range. Cooling of sea water increased the latency of response to electric stimuli. Biological significance of the thermal sensitivity of the Lorenzini ampulla is discussed.