The Resting Potential of Rat`s Corneal Endothelial Cells

Abstract

 

Purpose

 

The mechanism whereby the cornea maintains its transparency is not known. This study aims to register the presence and to quantify the resting potential (RP) of endothelial corneal cells. To the best of our knowledge this seems to be the first work to systematically measure and quantify the RP of endothelial cells of the cornea.

 

Methods

 

We performed 30 experiments on corneal preparations of Sprague-Dawley rats (n=30). Immediately after decapitation the eyeballs were removed and sectioned near the limbus. The corneas were transferred to a chamber and infused with Balanced Salt Solution (BSS) driven by a peristaltic pump in order to maintain the BSS flowing at a rate from 0.8 to 0.85 ml/min. The temperature in the chamber was set at 30 °C by means of a thermostatic bath. BSS is composed of (mmol/l): Na⁺ 160.0; Cl^- 130.0; ^-HCO₃ 25.0; K⁺ 5.0; ^-H2PO₄ 3.0; Mg⁺⁺ 1.0; Ca⁺⁺ 1.0; Glucose 5.0, presenting a pH = 7.4 and 305 mOsm/Kg. The presence or absence of electrical signal was detected by recording its voltage variations through two pore electrodes delicately introduced into the cells and connected to a Grass polygraph. The statistical analysis was made by Graph Pad Prism 6.0.

 

Results

 

In the 30 experiments (30 eyes), the RP presented a mean of 40.60 with a standard deviation of 7.05 and a standard error of 1.29. The graphics below illustrate the findings.

 

Conclusions

 

Although many studies are still needed to understand the role of the endothelium in the transparency of the cornea, our results demonstrate: 1. the presence of the resting potential in the corneal endothelium cells 2. a mean of 40.60±7.05 mV for the resting potential of the rat’s corneal endothelial cells.

 

 

This graph shows the mean value at the center line, the standard deviation (SD) at the boxes, and the maximum and minimum values.

 

 

Keywords: 508 electrophysiology: non-clinical • 481 cornea: endothelium • 480 cornea: basic science