Morphological, total nucleic acid and total protein analyses of rat embryos cultured in supplemented and unsupplemented human serum.

Culture of explanted 9 1/2 day rat conceptuses for 48 hours (i.e. until 11 1/2 days) in 100% human serum supplemented only with glucose does not result in growth and development comparable to those conceptuses cultured for the same period in 100% rat serum. Significant differences were observed in the yolk sac diameter, crown-rump length, morphological score and total embryonic nucleic acid content. No difference was observed in the total embryonic protein content. A large proportion of the embryos cultured in glucose-supplemented human serum (100%) exhibited abnormalities of the neural tube. Supplementation of the human serum with glucose and 10% rat serum resulted in embryos showing higher indices of embryonic growth and differentiation (in all criteria of assessment) than those cultured in pure rat serum; no abnormalities were observed. The significance of better growth and differentiation of the conceptuses in human serum supplemented with glucose and 10% rat serum is discussed.