Evidence of circadian rhythm of electric discharge in Eigenmannia virescens system.
The gymnotid electric fish, Eigenmannia virescens, exhibits electric discharge rhythmicity both in alternate light-dark (LD; 12 h light, 12 h dark [LD 12:12]) and in constant dark (DD) conditions. It suggests that the electric discharge rhythm is under control of the circadian clock. The free-running periods (FRPs) of electric discharge rhythms at 21 degrees C in DD are greater than, but close to, 24 h. The maximum of the electric discharge in the Eigenmannia system peaks approximately at circadian time 6 (CT6) in the middle of the subjective day. The circadian oscillator in the system is temperature compensated. This original report reveals the relationship between electric discharge activity and the circadian pacemaker in Eigenmannia and provides an alternative system to investigate circadian rhythms in vertebrates.
Deng
T S
TS
Institute of Botany, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China.
Tseng
T C
TC
D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D004555:Electric Fish / Q000502:physiology*; D004594:Electrophysiology; D004780:Environment, Controlled; D017440:Photoperiod; D013696:Temperature