MENINGEAL CELLS ORGANIZE THE SUPERFICIAL GLIA LIMITANS OF THE CEREBELLUM AND PRODUCE COMPONENTS OF BOTH THE INTERSTITIAL MATRIX AND THE BASEMENT-MEMBRANE
J. Sievers et al., MENINGEAL CELLS ORGANIZE THE SUPERFICIAL GLIA LIMITANS OF THE CEREBELLUM AND PRODUCE COMPONENTS OF BOTH THE INTERSTITIAL MATRIX AND THE BASEMENT-MEMBRANE, Journal of neurocytology, 23(2), 1994, pp. 135-149
We have investigated the factors controlling both the morphological tr
ansformation of glial processes into endfeet and the deposition of ext
racellular matrix molecules into the overlying basement membrane by de
stroying meningeal cells over the hamster cerebellum by 6-hydroxydopam
ine administration on the day of birth. We report that within 24 h of
destruction of meningeal cells, the concentrations of fibrillary colla
gens types I, III and IV in the glia limitans externa and the associat
ed basement membrane molecules laminin, collagen type IV, and fibronec
tin are greatly diminished, resulting in the development of focal gaps
in the basement membrane. The immunohistochemical integrity of the ba
sement membrane is restored within 3 days over those surfaces of the f
olial apices where meningeal cells reappear. Likewise, the fibrillary
collagens of the associated interstitial matrix are re-established in
the same amounts as in controls. However, meningeal cells remain perma
nently absent from fissures and all extracellular matrix molecules tes
ted disappear from rostral cerebellar folia covered by the anterior me
dullary velum. Moreover, the glial endfeet make up the superficial gli
a limitans only on folial apices, while they disappear from the fissur
al surfaces. In primary cultures, meningeal cells produce the fibrilla
ry collagens type I, III, and VI, and the matrix molecules fibronectin
and laminin, collagen type IV, nidogen, and heparansulphate proteogly
can. These findings indicate that meningeal cells (i) produce molecula
r components of both the interstitial matrix and the basement membrane
, and (ii) are involved in the morphological transformation of glial f
ibres into the endfeet which constitute the superficial glia limitans.