Search Results
You are looking at 1 - 1 of 1 items for
- Author: V. K. Lamb x
- Refine by access: All content x
Search for other papers by V. K. Lamb in
Google Scholar
PubMed
Search for other papers by H. J. Leese in
Google Scholar
PubMed
Preimplantation mouse embryos exhibit growth at the blastocyst stage when there is a dramatic increase in protein content between days 4 and 5 after hCG treatment. This increase in protein synthesis requires the uptake of amino acids from the surrounding medium, but the consumption of individual amino acids present as a mixture has not been examined. We therefore measured the simultaneous depletion of 18 amino acids by mouse blastocysts in culture on days 4 and 5 after hCG treatment. Two culture media were used: one with amino acids present at concentrations largely based on those reported to give optimal rates of embryo development (M16/mix AA), and a second with the amino acids each at 0.1 mmol l−1 (M16/0.1 AA). After derivatization with o-phthaldialdehyde to yield highly fluorescent products, amino acid concentrations in the media were measured by HPLC. On day 4, seven amino acids were depleted from M16/mix AA at rates significantly greater than zero: aspartate, arginine, glycine, alanine, isoleucine, leucine and lysine; on day 5, nine amino acids were depleted at significant rates: aspartate, glutamate, asparagine, tyrosine, methionine, valine, phenylalanine, isoleucine and leucine. Average amino acid depletion from M16/mix AA was 32% greater on day 5 than on day 4. Aspartate, glutamate, arginine, isoleucine and leucine appeared to be the key amino acids sought by embryos on both days tested. Embryos grown in amino-acid-containing media appeared morphologically normal and their volume increased compared with embryos cultured in the absence of amino acids.
