Ultrastructure of Rabbit Synovial Membrane

Abstract

Two types of cells can be detected in the normal rabbit synovium. Type-A is characterized by a prominent Golgi system, while Type-B contains abundant rough endoplasmic reticulum. Many intermediate forms, showing both these features, were also present These cells are loosely arranged in a medium density matrix. In deeper zones of the synovium, the matrix mainly contains periodically banded collagen fibers; in the middle zone it contains mainly aperiodic fibers, and in the superficial zone it contains granular material. The matrix like the synovial cells is subject to wear and replacement, and the appearances seen suggest a breakdown of collagen fibers 1st to aperiodic fibers and then to granular material.