Publications by authors named "W Dauber"

Osmium postfixation is established as a routine procedure for transmission electron microscopy (TEM). On the one hand, this routine procedure leads to good results for TEM, but on the other hand results in blackened tissue samples that do not allow examination of any structures within the embedded tissue sample by a light microscope. Equivalent fixation results for TEM are achieved with imidazole-osmium postfixation, and with this postfixation method tissue is not blackened and can be transilluminated with point light sources.

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Honeycombs are regularly arranged networks of tubules in continuity with the T-system of the skeletal muscle fibre. Their occurrence is usually described in pathologically modified or cultivated muscle fibres. Here we describe the occurrence of honeycombs in macroscopic normal muscle fibres of healthy frogs.

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In the present investigation the sole plate area of motor end plates of the frog is ultrastructurally examined with different postfixation methods. We concentrated in this case on the proof of the smooth and rough sarcoplasmic reticulum of the sole plate. The relations of the smooth and rough sarcoplasmic reticulum to subsynaptic folds and the local T-system and its connections to diads and triads in the sole plate area are represented.

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Previous investigations of the T-system in skeletal muscle fibres described the inter-myofibrillar relationships between T-tubules and the sarcoplasmic reticulum. They disregarded the arrangement of the T-system in the myofibril-free sarcoplasm in the area of muscle fibre nuclei. In the present investigation, the T-system was filled by means of lanthanum incubation and the myofibril-free sarcoplasm was ultrastructural examined by means of thin (< or = 100 nm) as well as thick sections (> 300 nm-1 microm) with the electron microscope.

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Perisynaptic Schwann cells (PSCs), descendants of the myelinating Schwann cells, cover the axon terminal of the vertebrate motor endplate of the skeletal muscle fiber. PSCs are assumed to support the function of the axon terminal. This function suggests a net material transport in the direction of the axon terminal.

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