Changes in freeze-fractured mitochondrial membranes during spermatogenesis
Abstract
The mitochondria of germ cells in spermatogenesis, and the transformation of mitochondria from an orthodox form in spermatogonia to a condensed form in spermatids has been described and widely characterized by TEM. The morphological correlation of freeze-fractured mitochondrial membranes with the energetic states of mitochondria has also been described. The frequency by which the fracture plane following the inner or outer boundary membrane deviates by jumping from one to the other is higher in phosphorylating mitochondria than in non-phosphorylating mitochondria. The present study on replicas of freeze-fractured spermatogenic cells of the rat showed that the frequency of deflections of the fracture plane was lowest in spermatogonial mitochondria and increased in spermatocytes and spermatids. Our study seems to suggest that this method can be applied to tissue samples also after glutaraldehyde fixation.