Test tube experiments reveal that most of the routine fixatives for electron microscopy, i.e. metallic oxidants ( 0-0 a4 n d KMn04) as well as various aldehydes alone or in combination with metallic oxidants, react in vitro with a number of monoamines and monoamine analogues forming a precipitate. This reaction seems to occur between fixatives and amines also in tissues, thus offering possibilities to visualize at the ultrastructural level monoamine stores and storage sites in nervous and non-nervous tissues. There are, however, marked differences between monoamine stores in various tissues and also obvious differences in sensitivity between various fixation procedures. Some of these problems are discussed and a survey is given of fixation procedures developed for the visualization of intraneuronal monoamine stores. There is good evidence that the intraneuronal monoamines both in the peripheral and central nervous system are localized mainly to so-called granular vesicles of which two types seem to exist, small and large granular vesicles. Both types are present in all parts of the neuron and some aspects on possible differences in chemical composition, intraneuronal distribution, site of formation and function are briefly discussed. © 1971, Elsevier Ltd. All rights reserved.
HÖKfelt, T. (1971). Ultrastructural Localization of Intraneuronal Monoamines Some Aspects on Methodology. Progress in Brain Research, 34(C), 213–222. https://doi.org/10.1016/S0079-6123(08)63966-7