Lactate dehydrogenase isoenzymatic spectrum in preimplantation murine embryos

The spectrum of LDH isozymes was studied using different concentration of X-100 triton for enzyme extraction from the eggs and embryos, different systems of electrophoresis and different methods of staining electrophoregrams. Similar results were obtained in all cases. The mouse eggs and embryos were shown to contain only LDH-1; the treatment of oviducal fluid with X-100 triton strengthened the activity of LDH-4 and LDH-5. The detection of the activity of LDH-5 and hybrid isozymes appears to be related to the presence of oviducal fluid in the sample under study.