ISSN:
1432-1106
Schlagwort(e):
Cerebellum
;
Cell fractions
;
Nervous tissue
;
Cerebellum ultrastructure
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Medizin
Notizen:
Summary Subcellular particles from the cerebella of rats ranging in age from newborn to adult have been obtained and studied by electron microscopic procedures. The material was homogenized in sucrose and successive centrifugations yielded a heterogeneous “nuclear” pellet containing free nuclei and cell debris, and a microsomal-ribosomal fraction in which three zones were distinguished: (a) the top, consisting of microsomes; (b) the bottom, formed exclusively by ribosomes; and (c) the middle, by both constituents mixed together. The fraction was free of contamination by other particles. A third pellet obtained from the previous centrifugations was layered on a discontinuous Ficoll-sucrose gradient. After centrifugation it yielded six bands, named, from top to bottom, A-F. Fraction A contained uncontaminated myelin fragments. B was made up of synaptosomes and occasional free mitochondria. F was a fraction largely formed of intact mitochondria. Bands C, D and E located between B and F were mixtures of synaptosomes and free mitochondria. There were changes in the fractions related to the age of the animals. No fraction A was obtainable during the first ten postnatal days, the number of synaptic vesicles per synaptosome increased in fractions taken during the second week, and augmentation of mitochondrial cristae was noted during the first three weeks. The isolation of fractions of uniform myelin fragments, synaptosomes, mitochondria, and microsomes-ribosomes from the developing cerebellum extends the possibility of biochemical analysis at subcellular level during the histogenesis of this organ.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00234378
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