Effect of pregnancy-specific protein B on luteal cell progesterone, prostaglandin, and oxytocin production during two stages of the bovine estrous cycle.
This experiment was designed to evaluate the effects of pregnancy-specific protein B (PSPB) on luteal cell progesterone (P4), PGF2 alpha, PGE2, and oxytocin secretion. Corpora lutea were collected during the mid (d 10 to 12; n = 5) or late luteal (d 17 to 18; n = 5) stage of the estrous cycle. Large and small cells (1.5 x 10(5)/well) were treated with PSPB (0, 2.5, or 5.0 micrograms) and LH (0, 50, or 100 ng) in a 3 x 3 factorial arrangement. Cells were incubated for 18 h before adding treatments; after treatments, medium was collected at 6 and 12 h. During the 18-h pretreatment period, P4, PGF2 alpha, PGE2, and oxytocin production was similar between the prospective treatment groups. The PSPB did not affect P4 production. Stage of the cycle (stage) x time interaction (P < .001) indicated that mid-stage luteal cells produced more P4 than late-stage cells; regardless of stage, P4 decreased with time. The time x LH interaction (P < .001) revealed that at 6 and 12 h the 50- and 100-ng doses of LH increased P4 to greater than the 0-ng dose. Production of PGF2 alpha by mid-stage cells was similar among the three PSPB treatments; however, PGF2 alpha production by late-stage cells increased (P < .01) in response to the 5.0-micrograms dose of PSPB. The LH did not affect PGF2 alpha production. Late-stage luteal cells produced more (P < .001) PGF2 alpha than mid-stage cells during the 18-h pretreatment period and at 6, but not 12, h.(ABSTRACT TRUNCATED AT 250 WORDS)
Del Vecchio
R P
RP
Agriculture & Agri-Food Canada Research Centre, Brandon, Manitoba.
Sutherland
W D
WD
Sasser
R G
RG
D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000494:pharmacology*; D002417:Cattle / Q000378:metabolism* / Q000502:physiology; D002478:Cells, Cultured; D015237:Dinoprost / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D004971:Estrus / Q000378:metabolism* / Q000502:physiology; D005260:Female; D008184:Luteal Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000494:pharmacology; D010121:Oxytocin / Q000378:metabolism*; D011257:Pregnancy Proteins / Q000494:pharmacology*; D011374:Progesterone / Q000378:metabolism*; D011453:Prostaglandins / Q000378:metabolism*
D011257:Pregnancy Proteins; D011453:Prostaglandins; D011374:Progesterone; D010121:Oxytocin; D007986:Luteinizing Hormone; D015237:Dinoprost; D016282:Aspartic Acid Endopeptidases; C094766:pregnancy-associated glycoprotein 1; D015232:Dinoprostone