Abstract:
:We have described the currents flowing across the presynaptic membranes of the four median photoreceptors of the giant barnacle, Balanus nubilus, using a quasi-voltage clamp arrangement. Membrane potential, measured in the terminal region of one photoreceptor, was controlled in all four terminals by feedback current supplied through the nerve containing the photoreceptors' axons. The [Ca2+]o in the saline was reduced to decrease the Ca2+ current, enabling better voltage control, and tetraethylammonium ion (TEA, 20 mM) was added to block a fast voltage-dependent K+ conductance. Depolarizing voltage steps from the resting potential in the dark (-60 mV) evoked slow, inward Ca(2+)-dependent currents which could be blocked by Co2+, Mg2+, or Cd2+. The Ca2+ currents were followed by large outward currents that persisted for many seconds after the offset of moderate or large pulses. These tail currents increased in magnitude and duration with pulse duration and reversed at about -80 mV, consistent with previous evidence for a Ca(2+)-activated K+ conductance in this membrane. When the Ca(2+)-activated outward current was reduced to zero by increasing the [K+]o so as to set EK at -20 mV, and then stepping the voltage to this value, the step evoked a steady inward Ca2+ current. Thus, the Ca2+ current did not show voltage- or Ca(2+)-dependent inactivation. When Ba2+ was substituted for Ca2+, 500-ms depolarizing steps evoked steady inward currents but no outward currents. In any given experiment, the activation voltage of the Ca2+ or Ba2+ current did not depend on holding potential. At the barnacle photoreceptor's synapse, the postsynaptic cell adapts to maintained presynaptic voltage by a mechanism that is not understood. We conclude that neither Ca2+ current inactivation nor a shift in activation voltage with holding potential can account for this adaptation.
journal_name
Vis Neuroscijournal_title
Visual neuroscienceauthors
Hayashi JH,Stuart AEdoi
10.1017/s0952523800003667subject
Has Abstractpub_date
1993-03-01 00:00:00pages
261-70issue
2eissn
0952-5238issn
1469-8714pii
S0952523800003667journal_volume
10pub_type
杂志文章abstract::Extrastriate areas TEO and V4 have been associated with form and color vision. Area V4 has also been suggested to participate in processes concerned with attention, stimulus salience, and perceptual learning. In a continuing effort to elucidate the connectional interactions and microcircuitry of these areas, we descri...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800002480
更新日期:1994-05-01 00:00:00
abstract::Color vision impairment was examined in patients with type 2 diabetes mellitus (DM2) without retinopathy. We assessed the type and degree of distortions of individual color spaces. DM2 patients (n = 32), and age-matched controls (n = 20) were tested using the Farnsworth D-15 and the Lanthony D-15d tests. In addition, ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523806233546
更新日期:2006-05-01 00:00:00
abstract::The period of susceptibility for binocular depth vision was studied in kittens by subjecting them to periods of monocular deprivation beginning at different ages. In an initial study, we found that normally reared kittens can learn a depth-discrimination task much more rapidly when tested binocularly than monocularly,...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800000341
更新日期:1990-09-01 00:00:00
abstract::Anterograde transport of cholera toxin subunit B (CTb) was used to study the retinal projections in birds, with an emphasis on retinohypothalamic connections. Pigeons (Columbia livia) were deeply anesthetized and received unilateral intraocular injections of CTb. In addition to known contralateral retinorecipient regi...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800002376
更新日期:1994-05-01 00:00:00
abstract::The purpose of the present study was to examine the contributions made by cat posterior parietal cortex to the analyses of the relative position of objects in visual space. Two cats were trained on a landmark task in which they learned to report the position of a landmark object relative to a right or left food-reward...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800175042
更新日期:2000-09-01 00:00:00
abstract::The aim of this study was to assess the plasticity of human voluntary fixational eye movement control in relation to visual experience/chronic visual deprivation. Twelve blind adults participated (self-reported vision < or = light perception in each eye; age range = 23-56 years; visual experience range = 0-28 years; b...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523802194090
更新日期:2002-07-01 00:00:00
abstract::Embryonic chick retinal pigment epithelial (RPE) cells can undergo transdifferentiation upon appropriate stimulation. For example, basic fibroblast growth factor (bFGF) induces intact RPE tissue younger than embryonic day 4.5 (E4.5) to transdifferentiate into a neural retina. NeuroD, a gene encoding a basic helix-loop...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800171172
更新日期:2000-03-01 00:00:00
abstract::This study used the swept spatial-frequency method to compare retinal and cortical acuity in anesthetized young adult rhesus monkeys. Visual evoked potentials (VEPs) and pattern electroretinographic responses (PERGs) were recorded from 25 monkeys (age range: 4-12 years) anesthetized with a continuous infusion of propo...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523899164010
更新日期:1999-07-01 00:00:00
abstract::A new tissue slice preparation of the cuttlefish eye is described that permits patch-clamp recordings to be acquired from intact photoreceptors during stimulation of the retina with controlled light flashes. Whole-cell recordings using this preparation, from the retinas of very young Sepia officinalis demonstrated tha...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523805223106
更新日期:2005-05-01 00:00:00
abstract::Four experiments were performed to assess the effects of ON channel blockade with the glutamate analog 2-amino-4-phosphonobutyrate (APB) on brightness and contrast perception in monkeys. In Experiment 1, we demonstrate that stimuli brighter than background (incremental stimuli) appear less bright following ON channel ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s095252380001107x
更新日期:1994-01-01 00:00:00
abstract::The laminar and tangential organization of visual callosal projections of areas 17 and 18 were investigated in the adult ferret, using histochemical methods to visualize axonally transported horseradish peroxidase (HRP). Normal adult ferrets were given injections of HRP throughout one visual cortex or had gelfoam soak...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800006398
更新日期:1992-07-01 00:00:00
abstract::Thresholds for detection of light by a dark-adapted test eye were measured while the other, non-test eye was either similarly dark adapted or while it was exposed to an intense red adapting field. An interocular effect that depends on the retinal location of the test was found: compared to the threshold during binocul...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800005095
更新日期:1992-04-01 00:00:00
abstract::The abundance and spatial distribution of retinal cone photoreceptors change during thyroid hormone (TH)-induced and natural development of rainbow trout (Oncorhynchus mykiss). These changes are thought to allow the fish to adapt to different photic environments throughout its life history. To date, the ontogeny of ra...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523806232139
更新日期:2006-03-01 00:00:00
abstract::The purpose of the present study was to compare standard multifocal visual evoked potential (mfVEP) pattern-reversal responses with those produced by pattern-onset, pattern-offset, and pulsed pattern stimuli. mfVEP recordings were obtained from five normal subjects using VERIS and a 4-electrode array. The standard rev...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523808080954
更新日期:2009-03-01 00:00:00
abstract::Increment threshold functions of the electroretinogram (ERG) b-wave were obtained from goldfish using an in vivo preparation to study intraretinal mechanisms underlying the increase in perceived brightness induced by depletion of retinal dopamine by 6-hydroxydopamine (6-OHDA). Goldfish received unilateral intraocular ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s095252380000300x
更新日期:1994-07-01 00:00:00
abstract::To explore the possible influence of defined genetic backgrounds on photoreceptor viability and function in mice carrying a targeted disruption of the rhodopsin gene, the severities of retinopathies in Rho-/- mice on C57BL/6J and 129Sv congenic backgrounds were compared by light microscopy and electroretinography and ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523801183100
更新日期:2001-05-01 00:00:00
abstract::Within the visual cortex of several mammalian species, more circuitry is devoted to the representation of vertical and horizontal orientations than oblique orientations. The sensitivity of this representation of orientation preference to visual experience during cortical maturation and the overabundance of cardinal co...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523804041045
更新日期:2004-01-01 00:00:00
abstract::The sudden displacement of the retinal image during a saccade raises the visual threshold of human observers to foveal stimuli. The fall in visual sensitivity observed during this phenomenon, known as saccadic suppression, seems to occur very early in the visual processing chain. The lateral geniculate nucleus (LGN) i...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523898155128
更新日期:1998-09-01 00:00:00
abstract::We tested the hypothesis that gamma-aminobutyric acid (GABA) is the transmitter released by barnacle photoreceptors onto postsynaptic cells (I-cells). GABA was applied to I-cells either by superfusion or by ejecting it with pressure from a pipette positioned close to the I-cell's soma. The I-cell's response to GABA wa...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800005496
更新日期:1989-10-01 00:00:00
abstract::Population-based studies of retinal neurons have helped to reveal their natural types in mammals and teleost fishes. In this, the first such study in a frog, labeled ganglion cells of the mesobatrachian Xenopus laevis were examined in flatmounts. Cells with large somata and thick dendrites could be divided into three ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s095252380001155x
更新日期:1997-09-01 00:00:00
abstract::The eye has become an excellent target for gene therapy, and gene augmentation therapy of inherited retinal disorders has made major progress in recent years. Nevertheless, a recent study indicated that gene augmentation intervention might not stop the progression of retinal degeneration in patients. In addition, for ...
journal_title:Visual neuroscience
pub_type: 杂志文章,评审
doi:10.1017/S0952523814000194
更新日期:2014-09-01 00:00:00
abstract::Contrast adaptation occurs in both the retina and the cortex. Defining its spatial dependence is crucial for understanding its potential roles. We thus asked to what degree contrast adaptation depends on spatial frequency, including cross-adaptation. Measuring the pattern electroretinogram (PERG) and the visual evoked...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523802195095
更新日期:2002-09-01 00:00:00
abstract::It is widely accepted that human color vision is based on two types of cone-opponent mechanism, one differencing L and M cone types (loosely termed "red-green"), and the other differencing S with the L and M cones (loosely termed "blue-yellow"). The traditional view of the early processing of human color vision sugges...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523801181125
更新日期:2001-01-01 00:00:00
abstract::GABA is a major inhibitory neurotransmitter in the mammalian retina and it acts at many different sites via a variety of postsynaptic receptors. These include GABAA receptors and bicuculline-resistant GABAC receptors. The release of acetylcholine (ACh) is inhibited by GABA and strongly potentiated by GABA antagonists....
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800011652
更新日期:1997-09-01 00:00:00
abstract::The development of spatial vision is relatively well documented in human and nonhuman primates. However, little is known about the development of sensitivity to motion. We measured the development of sensitivity to direction of motion, and the relationship between motion and contrast sensitivity in macaque monkeys as ...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523804216054
更新日期:2004-11-01 00:00:00
abstract::Five lagged cells were recognized by extracellular recording in the lateral geniculate nucleus of an awake, behaving macaque monkey. Previous reports of lagged cells were all in the anesthetized cat. Both parvocellular and magnocellular lagged cells were observed. Response timing was distributed continuously across th...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523808080784
更新日期:2008-09-01 00:00:00
abstract::Neighboring retinal ganglion cells often spike synchronously, but the possible function and mechanism of this synchrony is unclear. Recently, the strength of the fast correlation between ON-OFF directionally selective cells of the rabbit retina was shown to be stimulus dependent. Here, we extend that study, investigat...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/S0952523807070757
更新日期:2007-11-01 00:00:00
abstract::We investigated whether regenerating mature axons recapitulate embryonic features essential to successful reconnectivity within the injured nervous system. Strips from embryonic and adult chick retinae were cultured, and outgrowing axons were examined morphometrically and immunohistochemically. In addition, the target...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800002558
更新日期:1991-06-01 00:00:00
abstract::To date, two cannabinoid receptors, CB1 and CB2, have been cloned. The CB1 receptor has been found in a variety of tissues, particularly in the brain. CB2 receptor mRNA is mainly expressed in the immune system, though one group has found it in mouse cerebellum. Previous immunostaining studies in our lab demonstrated t...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800171093
更新日期:2000-01-01 00:00:00
abstract::Although excitotoxins derived from acidic amino acids are known to damage neurons in the inner nuclear and ganglion cell layers of the retina, little is known about their effects on photoreceptors. This study examines the acute and long-term effects of excitotoxins on photoreceptors of the chick retina. The zinc-iodid...
journal_title:Visual neuroscience
pub_type: 杂志文章
doi:10.1017/s0952523800001152
更新日期:1989-01-01 00:00:00