Date of this Version
Hoffman, K. Cupp, A. 2021. Effect of Elimination of Vascular Endothelial Growth Factor A (VEGFA) in Granulosa Cells on Concentrations of Anti-Mullerian Hormone and Follicle Stages in Mice. Undergraduate Honors Thesis. University of Nebraska - Lincoln.
Previous research demonstrated that eliminating VEGFA in granulosa cells caused follicle arrest, reduced ovulation rate and fertility in conditional knockout (KO) mice. Therefore, the hypothesis of the current research was that concentrations of Anti-Mullerian Hormone (AMH) would be increased in these VEGFA-granulosa conditional KO mice contributing to follicular arrest. Homozygous Vegfa-floxed mice were mated to mice whose genomic DNA genotyped positively for the Sry-Cre allele. The resulting litters were genotyped as wildtype (Control) or knockout (KO). The control mice are negative for the Sry-Cre allele and the KO mice are Sry-Cre;Vegfa-/- . During mouse dissections, we collected blood plasma, ovaries, uteri, kidneys, and adrenals and determined body weight and weights of all organs from control and Sry-Cre;Vegfa-/- KO mice that were 15, 30, and 60 days old. Enzyme-linked immunosorbent assays (ELISA) for AMH were conducted with blood plasma from each mouse genotype. The control and Sry-Cre;Vegfa-/- mice had different secretion of AMH concentrations over time with decreased AMH secretion in Sry-Cre;Vegfa-/- KO mice by 60 days (PSry-Cre;Vegfa-/- KO mice compared to controls at 30 and 60 days (P = 0.04) which maybe due to reduced follicle progression to antral stages in the KO mice. There was a difference in kidney weight at Day 15 (P = 0.05), however, weight of kidneys was not different at 30 and 60 days. There were no differences in uteri nor adrenals or body weight over genotype or collection, suggesting that the effect of elimination of Vegfa was specific to the ovary. Since AMH is produced by granulosa cells the reduced AMH production in the Sry-Cre;Vegfa-/- KO mice may be a marker of reduced granulosa cell function. Also Sry-Cre;Vegfa-/- KO mice have reduced fertility which may be due to decreased granulosa cell function, delayed follicle development leading to reduced numbers of ovulations, pups per litter and decreased number of parturitions shortening their reproductive lifespan.