Participation of phosphofructokinase, malate dehydrogenase and isocitrate dehydrogenase in capacitation and acrosome reaction of boar spermatozoa.

RODRIGUEZ PC; BREININGER E; SATORRE MM; DUBOIS D; CETICA PD; PEREYRA V

REPRODUCTION IN DOMESTIC ANIMALS (1990)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2017 vol. 52 p. 731 - 740

0936-6768

The aim of this work was to determine the enzymatic activity of phosphofructokinase(PFK), malate dehydrogenase (MDH) and isocitrate dehydrogenase (IDH) in boar spermatozoaand study their participation in bicarbonate-inducedcapacitation and follicularfluid-inducedacrosome reaction. Enzymatic activity of these enzymes wasdetermined spectrophotometrically in extracts of boar spermatozoa. Sperm suspensionswere incubated in the presence of bicarbonate (40 mM), a well-knowncapacitationinducer, or follicular fluid (30%), as an acrosome reaction inducer, and differentconcentrations of oxoglutarate, oxalomalate and hydroxymalonate, inhibitors of PFK,IDH and MDH, respectively. Capacitation percentages were determined by the fluorescencetechnique of chlortetracycline (CTC), and true acrosome reaction was determinedby trypan blue and differential?interferential contrast, optical microscopy. Theactivity of PFK in boar spermatozoa enzymatic extracts was 1.70 ± 0.19 U/1010 spermatozoa,the activity of NAD-andNADP-dependentIDH was 0.111 ± 0.005 U/1010and 2.22 ± 0.14 U/1010 spermatozoa, respectively, and the activity of MDH was4.24 ± 0.38 U/1010 spermatozoa. The addition of the specific inhibitors of these enzymesprevented sperm capacitation and decreased sperm motility during capacitationand inhibited the acrosome reaction (AR), without affecting the sperm motilityduring this process. Our results demonstrate the participation of PFK, IDH and MDHin bicarbonate-inducedcapacitation and follicular fluid-inducedacrosome reaction inboar spermatozoa, contributing to elucidate the mechanisms that produce energy necessaryfor these processes in porcine spermatozoa.