Expression of Cu/Zn and Mn superoxide dismutases during bovine embryo development: influence of in vitro culture.

in Molecular Reproduction and Development (2001), 58(1), 45-53

Temporal pattern of expression of Cu/Zn and Mn superoxide dismutases (SODs) was investigated in bovine oocytes and embryos produced in vitro in two different culture conditions and in vivo after ... [more ▼]

Temporal pattern of expression of Cu/Zn and Mn superoxide dismutases (SODs) was investigated in bovine oocytes and embryos produced in vitro in two different culture conditions and in vivo after superovulation. SODs were examined at a transcriptional level in single oocytes and embryos by reverse transcriptase-polymerase chain reaction (RT-PCR) and, at a protein level, by Western blotting on pools of embryos. mRNA encoding Cu/Zn SOD were detected in in vitro bovine embryos throughout preattachment development as well as in in vivo derived morulae and blastocysts. Transcripts for Mn SOD gene were detected in most immature and in vitro matured oocytes as well as in some zygotes and 5- to 8-cell embryos while no transcript was found at the 9-to 16-cell stage in both culture conditions. In vitro embryonic expression of Mn SOD was detected earlier in the presence of serum. Half of the morulae showed the transcript if cultured with 5% serum while none without serum. At the blastocyst stage Mn SOD could be detected independently of culture conditions. For in vivo-derived embryos Mn SOD transcripts were detected both in morulae and blastocysts. Immunoblotting analyses revealed that Cu/Zn SOD and Mn SOD were also present at a protein level in in vitro-derived zygotes and blastocysts. Together these data demonstrate, for the first time, that Mn SOD is transcribed and that Cu/Zn and Mn SOD proteins are expressed in preimplantation bovine embryos. Finally, they suggest that Mn SOD transcription is altered by in vitro culture conditions. [less ▲]

Evolution du taux de cortisol plasmatique chez le veau de la naissance à l'âge de 14 jours

in Comptes Rendus de l'Académie des Sciences de Paris (1977), 285

Plasma cortisol was recorded in 15 calves from birth to 14 days of age by a radioimmunoassay technique. At birth mean cortisol value is 67.3 ng/ml; 6 hours later it decreases by 58.4% then it gradually ... [more ▼]

Plasma cortisol was recorded in 15 calves from birth to 14 days of age by a radioimmunoassay technique. At birth mean cortisol value is 67.3 ng/ml; 6 hours later it decreases by 58.4% then it gradually diminishes and about 14 days after, it reaches adult levels (5.1 ng/ml). [less ▲]