マウス頭蓋骨内側表面の細胞の細胞内微細構造の走査型電子顕微鏡による観察の試み

Abstract

The cytoskeleton and plasmalemmal undercoat of bone-surface cells, especially of osteoclasts, have been studied in detail mainly by fluorescence microscopy and transmission electron microscopy, but its three-dimensional organization and its changes under various hormonal or pathological conditions have not fully been understood. To observe the three-dimensional organization of intracellular structures of the bone-surface cells by high resolution scanning electron microscopy (SEM), we used a new method of tissue-preparation for SEM. Parietal bones of the neonatal mice were removed and the inner-surface cells of those were mechanically raptured. Then, the free surface plasmalemma of the cells was detached by adhering it to the polylysine-coated glass. These bones were fixed, dehydrated, and dried by the critical point drying method. In the cells which had morphological characteristics of osteoblasts, filamentous networks of cytoskeleton were observed. These filaments were about 10nm or less in diameter and, thus, were thought to be actin filaments and intermediate filaments. Three-dimensional organization of filamentous networks was more obvious in stereopair micrographs. Membranous organelles to which the filaments attached were also observed.