title: Changes in the reproductive function and developmental phenotypes in mice following intramuscular injection of an activin betaA-expressing plasmid.
abstract: BACKGROUND
  The TGF-beta family protein activin has numerous reported activities with some uncertainty in the reproductive axis and development. The precise roles of activin in in vivo system were investigated using a transient gain of function model.
  
  
  METHODS
  To this end, an expression plasmid, pCMV-rAct, with the activin betaA cDNA fused to the cytomegalovirus promoter, was introduced into muscle of the female adult mice by direct injection.
  
  
  RESULTS
  Activin betaA mRNA was detected in the muscle by RT-PCR and subsequent Southern blot analysis. Activin betaA was also detected, and western blot analysis revealed a relatively high level of serum activin with correspondingly increased FSH. In the pCMV-rAct-injected female mice, estrus stage within the estrous cycle was extended. Moreover, increased numbers of corpora lutea and a thickened granulosa cell layer with a small antrum in tertiary follicles within the ovary were observed. When injected female mice were mated with males of proven fertility, a subset of embryos died in utero, and most of those that survived exhibited increased body weight.
  
  
  CONCLUSIONS
  Taken together, our data reveal that activin betaA can directly influence the estrous cycle, an integral part of the reproduction in female mice and activin betaA can also influence the embryo development as an endocrine fashion.
authors.affiliation: Department of Life Science/Research Center for Biopharmaceutical Lead Molecule, The Catholic University of Korea, Bucheon, Korea. beautymn@hanmail.net
authors.forename: Mi-Nyeu
authors.initials: MN
authors.lastname: Kim
authors.forename: Moon Nyeo
authors.initials: MN
authors.lastname: Park
authors.forename: Hoi Kyung
authors.initials: HK
authors.lastname: Jung
authors.forename: Chunghee
authors.initials: C
authors.lastname: Cho
authors.forename: Kelly E
authors.initials: KE
authors.lastname: Mayo
authors.forename: Byung-Nam
authors.initials: BN
authors.lastname: Cho
mesh_terms: D028341:Activins / Q000097:blood; D000818:Animals; D015139:Blotting, Southern; D001835:Body Weight; D047108:Embryonic Development; D030762:Estrous Cycle / Q000502:physiology*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D028322:Inhibin-beta Subunits / Q000235:genetics*; D007273:Injections, Intramuscular; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010053:Ovary / Q000166:cytology / Q000254:growth & development*; D010957:Plasmids / Q000008:administration & dosage; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D012098:Reproduction / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013737:Testis / Q000166:cytology; D013997:Time Factors
chemical_list: D012333:RNA, Messenger; C103008:inhibin beta A subunit; D028341:Activins; D005640:Follicle Stimulating Hormone; D028322:Inhibin-beta Subunits