RESUMO
Caput epididymal wild-type spermatozoa and cauda epididymal spermatozoa from mice null for the adenylyl cyclase Adcy10 gene are immotile unless stimulated by a membrane-permeant cyclic AMP analogue. Both types of spermatozoa exhibit flagellar angulation where the head folds back under these conditions. As sperm proteins undergo oxidation of sulfhydryl groups and the flagellum becomes more stable to external forces during epididymal transit, we hypothesized that ADCY10 is involved in a mechanism regulating flagellar stabilization. Although no differences were observed in global sulfhydryl status between caput and cauda epididymal spermatozoa from wild-type or Adcy10-null mice, two-dimensional fluorescence difference gel electrophoresis was performed to identify specific mouse sperm proteins containing sulfhydryl groups that became oxidized during epididymal maturation. A-kinase anchor protein 4, fatty acid-binding protein 9 (FABP9), glutathione S-transferase mu 5 and voltage-dependent anion channel 2 exhibited changes in thiol status between caput and cauda epididymal spermatozoa. The level and thiol status of each of these proteins were quantified in wild-type and Adcy10-null cauda epididymal spermatozoa. No differences in the abundance of any protein were observed; however, FABP9 in Adcy10-null cauda epididymal spermatozoa contained fewer disulfide bonds than wild-type sperm cells. In caput epididymal spermatozoa, FABP9 was detected in the cytoplasmic droplet, principal piece, midpiece, and non-acrosomal area of the head. However, in cauda epididymal spermatozoa, this protein localized to the perforatorium, post-acrosomal region and principal piece. Together, these results suggest that thiol changes during epididymal maturation have a role in the stabilization of the sperm flagellum.
Assuntos
Adenilil Ciclases/genética , Epididimo/química , Flagelos/fisiologia , Espermatozoides/química , Compostos de Sulfidrila/química , Proteínas de Ancoragem à Quinase A/química , Animais , AMP Cíclico/análogos & derivados , AMP Cíclico/metabolismo , Dissulfetos/química , Epididimo/embriologia , Epididimo/crescimento & desenvolvimento , Proteínas de Ligação a Ácido Graxo/química , Glutationa Transferase/química , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxirredução , Espermatozoides/crescimento & desenvolvimento , Espermatozoides/metabolismo , Canal de Ânion 2 Dependente de Voltagem/químicaRESUMO
Natural mating deposits a large number of sperm in a high volume of seminal plasma. Semen processed for AI has the seminal plasma greatly diluted, and processing of boar sperm for cryopreservation removes all seminal plasma. Boar sperm were evaluated for the impact of seminal plasma on the functional status of boar sperm. Seminal plasma prevented or reversed capacitation in frozen-thawed boar sperm. However, supplementing frozen-thawed semen doses with 10% seminal plasma did not significantly affect the number of sperm found in the utero-tubal sperm reservoir, nor did it affect farrowing rates.
