Related Experiment Video
Updated: Jul 25, 2026

Serial Enrichment of Spermatogonial Stem and Progenitor Cells (SSCs) in Culture for Derivation of Long-term Adult Mouse SSC Lines
Published on: February 25, 2013
Arrested germ cell divisions in the ageing human testis
1Institute of Anatomy, University of Bonn, Bonn, Germany. a.miething@uni-bonn.de
Abstract:
Arrested divisions represent a defective type of germ cell division. The cells are irreversibly arrested in a state marked by strongly condensed chromosomes, a dissolved nuclear envelope and a disturbed spindle apparatus. They finally die. The present ultrastructural study of the ageing human seminiferous epithelium is the first to describe such cells in the human testis. The cells usually lie in small groups and show intercellular bridges connecting them. The bridges lack a bridge-partitioning complex, a structure otherwise characteristic for bridges between dividing germ cells of a clone. Frequently, arrested divisions show signs of cytoplasmic disorganization and severe structural degradation. Centrioles, irregular microtubules, small membranous vesicles and granular electron-dense material are crowded within the circle of chromosomes. Some cells show numerous small vesicles and larger membranous structures distributed throughout the cytoplasm. The presence of arrested germ cell divisions in ageing men might be connected with local dysfunctions of the Sertoli cell barrier, which are known to appear focally in the ageing human seminiferous epithelium as well.
Related Concept Videos
Spermatogenesis
Replicative Cell Senescence
Meiosis I
Prophase I is the most extended and complex step of meiosis I characterized by synapsis, chromosome pairing, and recombination of the homologous chromosomes. This process is facilitated by a proteinaceous structure called the...
Meiosis II
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
Nondisjunction
Spermatogenesis
The process of spermatogenesis can be divided into mitosis, meiosis, and spermiogenesis. During mitosis, the spermatogonia or stem cells divide to produce two identical daughter cells, type A and B spermatogonia. Type-A...

