Direct assay of bound sialic acids
نویسندگان
چکیده
Bound sialic acids on rat spermatozoa were assayed by oxidation with 1 mMNaIO4 at 0\s=deg\C,liberating C-9 as formaldehyde which was further quantitated using 3\x=req-\ methyl-2-benzothiazolinone. The mean \m=+-\s.d. (n = 20) content of bound sialic acids of spermatozoa from the caput and cauda epididymidis was 50\m=.\9 \m=+-\8\m=.\0and 25\m=.\2 \m=+-\3\m=.\8 nmol/108 spermatozoa respectively. About 85% of the former and 75% of the latter could be extracted by 1% Triton X-100 and 2 mM-dithiothreitol. About 70% of the former and 20% of the latter were released by neuraminidase from Vibrio cholerae. About 40% of the former and 30% of the latter were sensitive to trypsin. During sperm maturation, the decrease in the total bound sialic acids was due to the decrease in the neuraminidase-sensitive but not the neuraminidase-resistant sialic acids.
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