retinal pigment epithelium lipofuscin

Introduction

The major component of lipofuscin in pigment epithelium is N-retinylidine-N-retinyl ethanolamine, formed from reaction of ethanolamine or phosphatidylethanolamine with retinaldehyde in disc membranes of photoreceptor outer segments. After the shed discs are phagocytosed by the retinal pigment epithelium, the molecule loses its phosphoglyceroid moiety to leave N-retinylidine-N-retinyl ethanolamine. This amphoteric quaternary amine is precisely the type of compound predicted to accumulate within lysosomes.

More general terms

• lipofuscin