[Abstract Title]. - Society for Neuroscience

Support: MA 037
Title: Process formation in astroglia: scanning electron microscopy study
Authors: *E. M. ABD-EL-BASSET;
Dept Anat, Kuwait Univ. Fac Med., Safat 13100, Kuwait
Abstract: This study describes and compares the appearance of astroglia and their processes
during the differentiation of astroglia in colony cultures before and after treatment of astroglia
with dibutyryl cyclic AMP (dBcAMP) and Cytochalasin D (CD) using scanning electron
microscopy. The small cells (SC) in the center of astroglia colonies had many microvilli near the
intercellular junctions. More peripheral medium sized cells (MC) and the large cells (LC) had
many thin processes that were in contact with those of adjacent cells. The surface of the cell
body in region adjacent to the processes had folds and blebs. The LC at the periphery of the
colony had similar folds and blebs proximally from the lamellipodia which extended from their
free surface. The mature small stellate astrocytes (SSA) had fewer, thicker and longer processes
some of which branched and/or ended in resembling structures growth cones. When the astroglia
were treated with dBcAMP the cells also acquired many thin processes which were similar to
those seen in untreated MC and LC. In addition the cell body had complete or incomplete
circular folds in the region from which the processes radiated. When both the untreated and the
dBcAMP-treated astroglia were exposed to CD the thin processes disappeared and the cells
acquired long thick processes instead. The formation of the thin processes in astroglia during
their differentiation in colony cultures and after treatment with dBcAMP may be due to
polymerization of actin filament bundles at the cell periphery followed by retraction of the
cytoplasm away from these bundles. However, the formation of the much longer and thicker
processes in SSA and CD treated cells after disassembly of actin filaments may instead be due to
the retraction of cytoplasm away from the bundles of the more stable intermediate filaments (IF)
which then persist in the longer processes.
Disclosures: E.M. Abd-El-Basset , None.
Poster
241. Glial Neuronal Interactions
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 241.14/G8
Topic: B.11.b. Cell biology and signalling
Support: OMHF