The effects of temperature on the dark-adapted spectral sensitivity function of the adult zebrafish.
In goldfish and other cold-blooded vertebrates, temperature can influence the rhodopsin/porphyropsin contributions to the rod photoreceptors. This study examined the effects of temperature on the spectral sensitivity function of the dark-adapted zebrafish. Zebrafish were housed in either a warm (28-30 degrees C) or cold (22-25 degrees C) tank prior to testing. Fish were dark-adapted for at least 1 h and electroretinogram (ERG) responses to 200 ms stimuli of various wavelengths and irradiances were obtained. Results show that water temperature affected the spectral sensitivity function of the ERG b-wave. Subjects housed in the warm temperatures had a spectral sensitivity consistent with the rhodopsin absorption curve; however, fish housed in the colder temperatures had a spectral sensitivity function that was the result of a rhodopsin/porphyropsin mixture. In addition, ultraviolet cones (lambda max: 362 nm) contributed to the dark-adapted spectral sensitivity function under both temperature conditions. Consistent with the results from other fish, the dark-adapted visual system of the zebrafish can be influenced by water temperature. The results of this study demonstrate the necessity of maintaining a stable environment when examining the contributions of the photoreceptors to the visual response.
Saszik
S
S
Department of Psychology, Western Kentucky University, Bowling Green 42101, USA.
Bilotta
J
J
D000221:Adaptation, Ocular / Q000502:physiology*; D000818:Animals; D004596:Electroretinography; D005260:Female; D008297:Male; D010775:Photic Stimulation; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology; D012168:Retinal Pigments / Q000502:physiology*; D017948:Retinal Rod Photoreceptor Cells / Q000502:physiology; D012243:Rhodopsin / Q000502:physiology; D013696:Temperature; D015027:Zebrafish / Q000502:physiology*
D012168:Retinal Pigments; C010507:porphyropsin; D012243:Rhodopsin