Retinal adaptation to dim light vision in spectacled caimans (Caiman crocodilus fuscus): Analysis of retinal ultrastructure.

It has been shown that mammalian retinal glial (Müller) cells act as living optical fibers that guide the light through the retinal tissue to the photoreceptor cells (Agte et al., 2011; Franze et al., 2007).

Corrigendum: Distribution of 28 kDa Calbindin-Immunopositive Neurons in the Cat Spinal Cord.

[This corrects the article on p. 166 in vol. 9, PMID: 26858610.

The ultrastructure of rabbit sclera after scleral crosslinking with riboflavin and blue light of different intensities.

Purpose: We aimed to determine the ultrastructural changes of collagen fibrils and cells in the rabbit sclera after scleral crosslinking using riboflavin and blue light of different intensities. Scleral crosslinking is known to increase scleral stiffness and may inhibit the axial elongation of progressive myopic eyes.

Methods: The equatorial parts of the sclera of one eye of six adult albino rabbits were treated with topical riboflavin solution (0.

Distribution of 28 kDa Calbindin-Immunopositive Neurons in the Cat Spinal Cord.

The distribution of vitamin D-dependent calcium-binding protein (28 kDa calbindin) was investigated in cat lumbar and sacral spinal cord segments (L1-S3). We observed specific multi-dimensional distributions over the spinal segments for small immunopositive cells in Rexed laminae II-III and medium-to-large cells of varying morphology in lamina I and laminae V-VIII. The small neurons in laminae II-III were clustered into the columns along the dorsal horn curvature.

Grouped retinae and tapetal cups in some Teleostian fish: occurrence, structure, and function.

This article presents a summary and critical review of what is known about the 'grouped retina', a peculiar type of retinal organization in fish in which groups of photoreceptor cell inner and outer segments are arranged in spatially separated bundles. In most but not all cases, these bundles are embedded in light-reflective cups that are formed by the retinal pigment epithelial cells. These cups constitute a specialized type of retinal tapetum (i.

Photonic crystal light collectors in fish retina improve vision in turbid water.

Despite their diversity, vertebrate retinae are specialized to maximize either photon catch or visual acuity. Here, we describe a functional type that is optimized for neither purpose. In the retina of the elephantnose fish (Gnathonemus petersii), cone photoreceptors are grouped together within reflecting, photonic crystal-lined cups acting as macroreceptors, but rod photoreceptors are positioned behind these reflectors.

Effects of intravitreal bevacizumab (Avastin) on the porcine retina.

Background: To evaluate the effects of intravitreal bevacizumab (Avastin) on the porcine retina, with respect to structural alterations, expression of proteins involved in apoptosis (bax, caspase-3, caspase-9) and gliosis (vimentin, GFAP), expression of factors which influence the development of vascular edema (VEGF, PEDF), and of membrane channels implicated in retinal osmohomeostasis (Kir4.1, aquaporin-1, aquaporin-4).

Methods: One eye of seven adult pigs received a single intravitreal injection of bevacizumab (1.

Dim light vision--morphological and functional adaptations of the eye of the mormyrid fish, Gnathonemus petersii.

The African weakly electric fish Gnathonemus petersii is well known for its electrosensory capabilities. These animals can detect and distinguish objects through active electrolocation in complete darkness. Because of their nocturnal lifestyle, a low contribution of vision for orientation and object detection has been expected.

Ischemia-reperfusion causes exudative detachment of the rabbit retina.

Purpose: To characterize the activation of macroglial (Müller) and microglial cells, as well as neuronal cell degeneration, during ischemia-reperfusion in rabbit retina and to test the possible effect of triamcinolone acetonide on gliosis.

Methods: Transient retinal ischemia was produced by increasing intraocular pressure for 60 minutes. Triamcinolone (8 mg) was intravitreally applied immediately after the cessation of ischemia.

Tandem-pore K(+) channels display an uneven distribution in amphibian retina.

Previous studies in retinal glial (Müller) cells have suggested that the dominant membrane currents are mediated by K(+) inward-rectifier (Kir) channels. After blockade of inwardly (Kir) and outwardly (KD and BK) conducting channels, a large K(+) conductance remains, but its nature has not been determined. Tandem-pore K(+) channels are likely candidates for this potassium conductance and the purpose of the present study was to determine, using immunocytochemistry, whether Müller cells express TASK-1, TASK-2, TREK-1 and/or TREK-2 potassium channel subunits.