Abstract
Abstract: :
Purpose: Newts possess the ability to regenerate a fully functional retina following complete removal of the original retina. Previously, we reported that progenitor cells in the early regenerating retinas are electrically coupled (Chiba and Saito J. Neurobiol. 42:258-269, 2000). The aim of this study is to examine changes in the gap junctions, and connexin expression during retinal regeneration of adult newt. Methods: We prepared living slice preparations of regenerating retinas at various stages and examined the degree of electrical and tracer coupling using whole-cell patch-clamp recording techniques. Regenerating retinas were also immunostained by antibodies against connexins. Results: We found that Cx43 is abundant between progenitor cells in the early regenerating retina. The degree of electrical and tracer couplings, and the amount of Cx43 gradually decreased as retinal regeneration proceeded. In the regenerated retina as well as normal retina, Cx43 was restricted in the distal end of Müller cells and pigment epithelial cells. Conclusion: This study provides morphological, physiological and immunohistochemical evidence that the degree of Cx43 expression is not a static phenomenon, but changes during regeneration.
Keywords: 416 gap junctions/coupling • 564 retinal development • 434 immunohistochemistry