Electron-microscopic studies of the axons of the posterior pituitary gland using the tannic acid reaction
Loesch, A.
Neuropatologia Polska 18(3): 483-496
1980
ISSN/ISBN: 0028-3894 PMID: 7432642 Document Number: 161487
The secretory axons of neurohypophysis in the rat were investigated after tannic acid fixation, and after the conventional fixation with glutaraldehyde and the ZIO [zinc-iodide-osmium] impregnation. On the basis of the reaction with tannic acid, 2 types of axons were distinguished. The A1 type axon is characterized by a presence of the neurosecretory granules which do not react with the tannic acid, that is, remain the same as after the conventional glutaraldehyde treatment. The A2 type reveals a presence of neurosecretory granules of the high electron density and reacting with tannic acid, as well as certain amount of the granules of the low electron density, whose membrane is sometimes impregnated with the product of reaction. The 2 distinguished categories of axons contain a different type of microvesicle. Tannic acid reaction facilitates detecting some morphological differences between some neuronal elements which could not be revealed by means of conventional methods.