RESUMO
Saimiri collinsi is used as an animal model in biotechnology research for conservation of species from the genus Saimiri. However, the development of biotechnologies depends on a proper knowledge of the sperm morphology to understand the basic aspects of sperm physiology, as potential male fertility depends on different cellular sperm structures. With this purpose, this study characterized the micromorphological and ultrastructural characteristics of squirrel monkeys (Saimiri collinsi) sperm using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM electromyography revealed that a normal Saimiri collinsi sperm measures 71.7 ± 0.7 µm with lateral tail insertion, a paddle-shaped flattened head and an acrosome occupying most of the head. TEM also showed that the middle piece is characterized by a central 9 + 2 microtubule axoneme surrounded by nine dense fibres, and that the mitochondria were juxtaposed, forming the mitochondrial sheath. Here we provide the first micromorphological and ultrastructure description of S. collinsi sperm.
Assuntos
Acrossomo/ultraestrutura , Cabeça do Espermatozoide/ultraestrutura , Cauda do Espermatozoide/ultraestrutura , Espermatozoides/ultraestrutura , Acrossomo/fisiologia , Animais , Axonema/ultraestrutura , Membrana Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica de Transmissão/métodos , Mitocôndrias/ultraestrutura , Sêmen/citologia , Cabeça do Espermatozoide/fisiologia , Motilidade dos Espermatozoides , Cauda do Espermatozoide/fisiologia , Espermatozoides/fisiologiaRESUMO
In the last decade, vitrification protocols to preserve human ovarian tissue have been regularly reported, even more often than the protocols developed for large mammals, such as ruminants and nonhuman primates. In order to facilitate the use of domestic ruminants (cows, goats, and sheep) and nonhuman primates as animal models, application of similar protocols as used for human material is performed. Next to it, the addition of indispensable or exclusion of avoidable compounds in the vitrification of human ovarian tissue should be tested in such experiments with animal models. The objective of this mini-review is to summarize the current protocols used for the vitrification of ovarian tissue and to evaluate the vitrification methods in humans, nonhuman primates, and domestic ruminants.