ISSN:
0362-2525
Schlagwort(e):
Life and Medical Sciences
;
Cell & Developmental Biology
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Biologie
,
Medizin
Notizen:
Spermatogenesis of the sea urchin Paracentrotus lividus has been studied at the ultrastructural level after conventional staining of thin sections and after en bloc silver staining. Cytoplasmic dense bodies are present in all steps of spermatogenesis except in late spermatids and spermatozoa. These bodies are closely associated with the development of centrioles and of the acrosomal vesicle during spermiogenesis. After it first appears, acrosomal vesicle is linked to the nuclear envelope by electron-dense material and subsequently acquires a dense core. Later the acrosomal vesicle moves to the apical pole of the cell while maintaining its connection to the nucleus. Although chromatin was highly condensed in the head of spermatozoa, one or more nuclear vacuoles within the nucleus were found to contain uncondensed chromatin fibers. Silver nitrate stains several nuclear and cytoplasmic structures. In the nucleus it stains the nucleolus, specific regions at the periphery of the chromatin, the synaptonemal complexes, the nuclear basal fossa, and the nuclear vacuoles of spermatozoa. In the cytoplasm, silver stains the cytoplasmic dense bodies, the material that connects the acrosomal vesicle to the spermatid nucleus, the spermatozoan subacrosomal and periacrosomal materials, the intercellular bridges of spermatids, and the centrioles. Silver staining is abolished by pretreatment with pronase E, suggesting that silver staining is due to protein.
Zusätzliches Material:
24 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/jmor.1051950205
