作者: XL Yang , K Tornqvist , JE Dowling
DOI: 10.1523/JNEUROSCI.08-07-02259.1988
关键词: Anatomy 、 Cell activity 、 Perch 、 Biophysics 、 Biology 、 Retina 、 Darkness 、 Electrophysiology 、 Carp 、 Membrane potential 、 Fish <Actinopterygii>
摘要: The effects of prolonged (greater than 2 hr) darkness and background illumination on the light responsiveness cone horizontal cells were examined in isolated, superfused white perch retinas. In retinas from fish maintained complete for more hr, had a resting membrane potential about -18 mV, they generated only slow, low-amplitude (3-4 mV) responses even when stimulated with bright flashes. Following presentation dim light, slowly hyperpolarized thereafter remained at level (about -25 mV). Concurrently, their dramatically enhanced size, response amplitudes to flashes eventually increased 50 mV. This was accompanied by noticeable changes waveforms; following exposure, became faster showed initial on-transients. increase cell graded intensity light. A similar enhancement occurred after presenting repetitively intervals 9 sec. sensitization phenomenon observed both L- C-type cells. When light-sensitized isolated long periods 30 min), gradually decreased. waveform opposite those that dark-adapted exposed lights; depolarized 5-7 mV light-evoked slower. Effects rod-driven as well. Rod log units sensitive recorded retinas, rod large (approximately mV), which could not be further illumination. Cone carp retina also depressed fashion retina. change amplitude 2-fold compared 5- 10-fold perch. These results indicate teleost is suppressed lights release suppression.(ABSTRACT TRUNCATED AT 400 WORDS)