Figure 6.

Mitochondrial activity, indicated by membrane potential, is impaired in absence of TXNRD3.A, dynamic representative of mitochondrial membrane potential (ΔΨm) indicated by Mitotracker. Mouse sperm were capacitated then stained with 500 nM Mitotracker Deep Red which accumulates ΔΨm-dependently. ΔΨm was dissipated by antimycin A—an inhibitor of electron transport chain during oxidative phosphorylation. B, transition of the mitochondrial membrane potential. The changes of fluorescence intensity were calculated as ΔF/F₀ (F₀, the mean fluorescence intensity of the sperm midpiece before adding antimycin A (at 10 s); F, the fluorescence of the midpiece after adding antimycin A; ΔF = F − F₀). Capacitated Txnrd3^−/− sperm show heterogeneous response to antimycin A, suggesting disrupted cellular respiration. C, ATP level from wild type and Txnrd3^−/− sperm before and after 90 min capacitation. 10 μM Antimycin A was added 30 min before sample collection. Statistical analyses between same genotype were performed using paired Student’s t test. Mean ± SD. ∗p < 0.05.