Cerebrospinal fluid activity of dynorphin-converting enzyme at term pregnancy.
Cerebrospinal fluid activity of a dynorphin-converting enzyme transforming prodynorphin-derived peptides to [Leu]enkephalin-Arg6 was measured in 12 women at term pregnancy before cesarean section and in eight nonpregnant, nonpuerperal controls. In pregnant women, the dynorphin-converting enzyme activity was significantly lower (mean +/- SD 6.8 +/- 3.8 U/L) than in nonpregnant controls (11.7 +/- 2.6 U/L; P less than .01). Furthermore, prodynorphin-derived [Leu]enkephalin-Arg6-containing polypeptides were significantly increased in samples from pregnant women (P less than .05). This indicates that a reduced activity of opioid peptide-degrading enzymes might contribute to an increased resistance to pain at term pregnancy.
D002585:Cesarean Section; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004399:Dynorphins / Q000378:metabolism*; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000134:cerebrospinal fluid; D004745:Enkephalins / Q000134:cerebrospinal fluid; D005260:Female; D006801:Humans; D008183:Luteal Phase; D011247:Pregnancy / Q000134:cerebrospinal fluid*; D011498:Protein Precursors / Q000134:cerebrospinal fluid; D011863:Radioimmunoassay / Q000379:methods; D012697:Serine Endopeptidases / Q000134:cerebrospinal fluid*
D004745:Enkephalins; D011498:Protein Precursors; D004743:Enkephalin, Leucine; D004399:Dynorphins; C026768:enkephalin-Leu, Arg(6)-; C033660:preproenkephalin; D012697:Serine Endopeptidases; C054870:dynorphin-converting endopeptidase