Imaging neurite outgrowth and cytoskeletal reorganization with an atomic force microscope: studies on pc12 and nih-3t3 cells in culture. Lal, Ratneshwar, Barney Drake, Deborah Blumberg, Donald Saner, Paul K. Hansma, Stuart C. Feinstein. Department of Medicine, University of Chicago, Chicago, IL 60637, Departments of Physics and Biology, University of California, Santa Barbara CA 93106.
APStracts 2:0134C, 1995.
An atomic force microscope was used to image the morphology and structural reorganization of rat NIH-3T3 fibroblasts and PC12 cells growing in petri dishes. NIH-3T3 fibroblasts had a uniform morphology and an extensive cytoskeletal network. Cell thickness varied from 2-3 m above the nucleus to 20-30 nm over the distal processes, and cytoskeletal fibers as small as 30 nm thick were observed. Imaging over an extended period of time showed a limited degree of cytoskeletal reorganization. Localized force-dissection did not induced significant retraction of cellular processes and immediate cell death. Differentiating PC12 cells with a neuronal phenotype had a non-uniform morphology, abundant cytoskeletal elements, neuritic processes and growth cones. The cell thickness varied from 5-8 m over the nucleus to 100-500 nm over the neuritic processes; growth cones 50-700 nm thick and end structures 30-150 nm thick were visible. Repeated imaging showed reorganization of the growth cone, especially the appearance and disappearance of bead-like features and fibrous organization. Thus an atomic force microscope can be used for high resolution, real-time studies of the dynamic sub-cellular mechanisms that drive cell behavior.

Received 23 August 1994; accepted in final form 20 January 1995.
APS Manuscript Number C500-4.
Article publication pending Am. J. Physiol. (Cell Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 21 March 1995.