69 ref. Sum. (En)

Although some information is available on the nutrient requirements of preimplantation stages of mammalian embryos, much more work is required to have a comprehensive knowledge of what these embryos need to develop in vitro, either for short periods of time during transfer or extended periods of time during manipulation. Until we have more information, a general medium for the cultivation of mammalian ova might consist of the following: (1) the salts contained in blood plasma, or Krebs-Ringer bicarbonate, (2) a sodium bicarbonate buffer with a concentration of approximately 25 Moles, (39 an atmosphere containing 5 percent CO2, in the gas phase, (4) a pH of approximately 7.4 which would be the result of items two and three, (5) a protein concentration of 1 to 10 mg/ml, (6) a glucose concentration of 1 mg/ml, (7) a pyruvate concentration of about 5 x 10 M. Supplementary compounds could be added to such a preparation, such as serum, embryo extracts, lactate, amino acids, vitamins and cofactors