Studies on deficiency of Schwann cell basal lamina and deformation of collagen fibres induced by beta-aminopropionitrile in cultures of developing rat peripheral neurons.

The morphological analysis in culture of superior cervical ganglia and dorsal root ganglia showed the following: (1) collagen fibres external to the neurite bundles were larger than those inside the neurite bundles in both control and BAPN-treated cultures; (2) there was much more irregularity of shape in external than in internal fibres in dorsal root ganglia with BAPN; (3) there was reduced basal lamina formation by Schwann cells in both types of ganglia (Okada & Bunge, 1981); (4) basal lamina formation in the superior cervical ganglion was reduced as the days of treatment with BAPN increased (from 94.7% with one day of treatment to 66.7% with 8 days of treatment; (5) in the dorsal root ganglion preparation, the myelin internode was shorter in BAPN (105.1 micron +/- 34.5 micron) than in control media (127.8 micron +/- 32.8 micron: P less than 0.001); (6) there was no significant difference in thickness of myelin between controls (2.9 micron +/- 0.9 micron) and those treated with BAPN (2.7 micron +/- 0.7 micron: 0.05 less than P less than 0.1); (7) the node of Ranvier was more elongated in BAPN (5.1 micron +/- 4.1 micron) than in control media (2.5 micron +/- 0.8 micron; P less than 0.01). The relationship between connective tissue abnormalities caused by BAPN and of the basal lamina formation of myelin-forming cells affected by BAPN is discussed.