神経膠細胞の培養

1．はじめに

　組織培養を始めて10年，その間共同研究者と共に目指した事は生きている脳の細胞を用いて，細胞の機能と形態の橋渡しをしたいと云う事であつた。機能と形態を検べて行く，これはいうべくして仲々に困難なことである。特に脳の如き色々な細胞が様々な配列で存在する組織では一つの細胞磯能を確めることは極めて難しい。

　今日お話しする神経膠細胞neurogliaには従来より星状膠細胞（astrocyte又はmacroglia）と僅突起膠細胞（oligodendrocyte）の2種類がある。この他小膠細胞micreogliaがあるがその組織球的細胞機能から厳密には前2者と一応区別して考えている。W．Penfield^32）の著"Cytology andCellular Pathology of the Nervous System"にastrocyteの機能は他臓器の結合織の如く脳の支柱系を司りpiaや血管と結び付き，又一度病変が起るとその障害部位の副木的役割をなすという。又oligodendrocyteはCajal^9）のいう所謂perineuronal satellitesで完全にneurenと共存を営みmyelinの形成にあずかるとされている。今日この考え方は根本的に修正される程の論議なくむしろ常識化されてさえいる。

The neuroglia and microglia cells are easily demonstrated in tissue culture preparation us-ing the hanging drop,roller tube, flask and Rose chamber methods.oligodendrocytes cul-tivated from the kitten and puppy showed rhy-thmic contractility.This analysis demonstrated that the contraction frequency was not signifi-cant difference between kitten and puppy ma-terial,age of the culture and length of resi-dence in perfusion chamber set up.Cine re-cords of these cultures perfused with nutrient medium containing 25γ/ml.chlorpromazine sho-wed rapid shrinkage and bubbling of the cy-toplasma puickly followed by an acceleration of the rate of contraction of all oligodendrocy-tes.Serotonin at 10γ/ml.also increased the frequency of contraction. However,simultaenous treatment of both drugs showed no increase in the activity of contracting oligodendrocytes.It appears,therefore,that these substances act antagonistically under these conditions.50γ/ ml.reserpine showed no change of the contra-ction rate.However,simultaenous administra-ted reserpine with serotonin stoped dramatica-lly the contraction of all oligodendrocytes, therefore the serotonin activated the action ofthe reserpine.Since the oligodendrocytes be-lieved to be the most numerous cell in the brain and to have a higher oxi dation metabo-lism in comparison with other kinds of cells, the effect of psychotropic drugs on the beha-vior of this element is of special interest.

Both types of astrocytes, protoplasmic and fibrous, are easily demonstrated in all brain culture. If using suspended cell culture me-thod, fibrous astrocytes remains constant, the-refore a pure culture of fibrous astrocytes is made. Along with the repetition of the passa-ge, the vital potentiality of fibrous astrocytes decrease gradually. When these cells are kept for more than 3 months after the 10th passage, the whole culture field presents itself with the network structure of astroglial processes even with the decrease of the cell bodies (gliafiber formation). Moreover, using the Rose chamber culture technique, the creased zone made in cellophane strip sets upon the culture mate-rials. For about 2 -3 weeks culture, astrocytes under the creased zone present a unbranched form, hypertrophy and slight hyperplasia. This behavior might be interpreted as a phe-nomenon of adaptation in young culture days.