https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:1978 region 7 > region 6 > region 1 > region 8 > ductuli efferentes), and orchidectomy had little effect on the rates. Incorporation into four proteins that were secreted in vitro (Mr 38 000, 20 000, 15 000, and 13 000) was reduced or abolished by orchidectomy and restored by testosterone therapy. The secretion of three proteins (Mr 52 000, 23 000, and 22 000) was reduced or abolished by orchidectomy and not restored by testosterone therapy. SDS-PAGE of detergent extracts of sperm indicated that five proteins were lost and nine were gained during epididymal transit. Seven of the proteins gained were about the same molecular weight as proteins secreted by the epididymis (Mr 94 000, 52 000, 38 000, 36 000, 22 000, 20 000, and 13 000) and were analyzed using N-terminal amino acid microsequencing.]]> Sat 24 Mar 2018 08:33:15 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:1595 Sat 24 Mar 2018 08:30:41 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:21182 Sat 24 Mar 2018 07:56:06 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:27633 L-tryptophan > L-tyrosine) were substrates for this enzyme, eliciting the dose- and time-dependent generation of ROS via mechanisms that were enhanced by cell death. This unexpected result was confirmed by analyses of ROS generation in subcellular sperm fractions, which again located a majority of LAAO activity to the sperm head. Equine cryopreservation medium was shown to contain sufficient quantities of aromatic amino acids to activate the LAAO system and generate ROS. The biological significance of this activity was established in an experiment in which physiological concentrations of aromatic amino acids were found to suppress sperm motility but only if dead spermatozoa were present in the same suspension. The combination of aromatic amino acids and nonviable cells was also found to enhance the levels of lipid peroxidation in live spermatozoa. These results suggest the potential significance of LAAO activity in generating the oxidative stress associated with the cryopreservation of equine spermatozoa. It is possible that inhibitors of this enzyme system may facilitate the development of modified cryostorage regimes for clinical validation in vivo.]]> Sat 24 Mar 2018 07:34:05 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:48643 Fri 24 Mar 2023 13:37:38 AEDT ]]>