Structure of retina in insectivorous Bat (Rhinopoma hardwickii( by electron microscope

The eye is the important sensory organ that the organism needs it for their surviving. In the present study, 5 male insectivore bats (Rhinopoma hardwickii) weighing of 8.1 ±0.3g were captured by mist net. The bats anesthetized and dissected their both eyes in the lab. After eye measuring, the sections (1 × 1 mm) were isolated from peripheral and central regions of the retina, fixed in 4% glutaraldehyde and 2% paraformaldehyde (1 hour) and rinsed with sodium cacodylate buffer (0.1) for 2×10 minutes. They were postfixed in osmium tetroxide 1% and washed with distilled water. After dehydration, clearing, infiltration in resin and embedding, the thin sections (70 mm) were placed on the copper grid, stained with uranyl acetate and lead citrate, and studied by transmission electron microscope. Findings showed that the ratio of the eye’s diameter to the body length in insectivore bat was 1: 27.11. The pattern of the retina was linear with two types of photoreceptor cells with dominant rods (mosaic pattern) and 4 type cells with different density and distribution. Bipolar cells had the most population especially in the central area of the retina. Retinal thickness was 206.51±22.07, and density of rod cells in the central area was more than peripheral. According to the results, the retinal pattern was as the other mammals and due to adaptation to dim light

کلیدواژه ها:

Bat ، Retina ، Adaptation ، Vision ، Electron microscope