Column chromatography and electrophoresis of bovine uterine lumenal proteins collected during the estrous cycle

Abstract

Uteri of 29 normally cycling Holstein and Jersey cows were non-surgically flushed with 50 ml sterile 1.5% saline, and fluids were recovered to evaluate biochemical methods for determination of qualitative changes in uterine lumenal protein at known stages of the estrous cycle. Total protein (mg) and number of red blood cells (million/ml) were 17.7 and 9.8; 7.6 and 7.1; 9.1 and 6.0; and 26.2 and 2.8 at day 0, 5, 10 and 15 of the bovine estrous cycle. Column chromatography (Sephacryl S-200) of uterine secretions revealed seven uterine specific peaks at ambient temperatures. One peak may be a hemoglobin contaminant. Five uterine specific protein peaks representing proteins greater than 160 000, ∼ 25 000 and less than 13 700 mol. wt. (3) were eluted with high performance liquid chromatography. Native polyacrylamide disc gel electrophoresis fractionated uterine fluid into as many as 13 bands. There were differences in six protein bands between uterine fluid and plasma. The consistency between Sephacryl S-200 and high performance liquid chromatography is the presence of three to four low molecular weight (< 13 700) uterine specific proteins. Sephacryl S-200 chromatography resulted in elucidation of a uterine specific protein approximately 60 000 mol. wt. not found with high performance liquid chromatography. However, proteins with mol. wt. > 160 000 and approximately 25 000 were found with high performance liquid chromatography. Results indicate no differences in protein class during the estrous cycle and that red blood cell contamination must be monitored during qualitative evaluation of uterine proteins.