Mitochondrial bioenergetics of testicular cells from the domestic cat (Felis catus)—A model for endangered species

Efficient spermatogenesis relies on the balance between energy production and expenditure, and thus depends on mitochondrial function. Our goal was to characterize testis mitochondria isolated from the domestic cat for their future use as a model for endangered felids. Respiration parameters were monitored with a Clark-type oxygen electrode, and the mitochondrial transmembrane potential (ΔΨ) was estimated with a TPP+ electrode. Testis mitochondria are shown to require low oxygen consumption to generate approximately the same maximum ΔΨ as other tissues. We also found differences between young and adult cats suggesting a less efficient phosphorylation system in the first group. Furthermore, an interpolation equation of the relation between maximum ΔΨ and age allowed the prediction of the expected ΔΨ at each age, as well as possible deviations. The results generate a novel model from a carnivore to further test drugs or environmental contaminants (such as pesticides and herbicides), many of which act on mitochondria and may interfere with the reproduction of wild animals.