Journal of Animal Science, Vol 68, Issue 7 2009-2014, Copyright © 1990 by American Society of Animal Science

JOURNAL ARTICLE

Relationship between plasminogen activator production and bovine embryo development in vitro

M. A. Kaaekuahiwi and A. R. Menino Jr
Dept. of Anim. Sci., Oregon State University, Corvallis 97331-6702.

The relationship of plasminogen activator (PA) production to cell stage, cell number and changes in overall diameter and zona pellucida thickness for bovine embryos developing in vitro was determined. Late morulae to blastocysts (n = 80) were collected nonsurgically from naturally mated, estrous-synchronized, superovulated crossbred beef cows. Embryos were cultured, one embryo per 25-microliters microdrop, for 6 d. At 24-h intervals, embryos were evaluated for stage of development and transferred to fresh microdrops; media were recovered for PA analysis. In addition, embryo diameter and zona pellucida thickness were measured with an ocular micrometer. Plasminogen activator production was determined using a caseinolytic assay with urokinase as the standard. Changes in diameter, zona pellucida thickness and PA production per 24-h interval for each embryo were plotted, and the graphs were cut out and weighed. Sixty-one embryos (76%) completed the hatching process. Total PA production was correlated positively (P less than .005) to embryonic size (r = .40), developmental stage (r = .35) and cell number (r = .35) and negatively, but weakly, correlated to zona pellucida thickness (r = -.13; P = .267). Hatched embryos produced more total PA than embryos that did not hatch (.140 +/- .011 vs .070 +/- .019 g; P less than .01). These results suggest that as embryonic size and cell number increase and development progresses, bovine embryos liberate more PA.

This article has been cited by other articles:

				K.-W. Park, S.-H. Choi, X.-X. Song, H. Funahashi, and K. Niwa Production of Plasminogen Activators (PAs) in Bovine Cumulus-Oocyte Complexes during Maturation In Vitro: Effects of Epidermal Growth Factor on Production of PAs in Oocytes and Cumulus Cells Biol Reprod, July 1, 1999; 61(1): 298 - 304. [Abstract] [Full Text]

				R. L. Krisher, M. Lane, and B. D. Bavister Developmental Competence and Metabolism of Bovine Embryos Cultured in Semi-Defined and Defined Culture Media Biol Reprod, June 1, 1999; 60(6): 1345 - 1352. [Abstract] [Full Text]