The involvement of luteinizing hormone (LH) and Pregnancy-Associated Glycoprotein family (PAG) in pregnancy maintenance in the pig.
The paper presents the effect of in vivo immuno-neutralization of porcine luteinizing hormone (pLH) by species-homologous porcine antiserum (anti-pLH) administrations on pregnancy maintenance and immunodetection of the PAG proteins in precipitated plasma proteins of pregnant gilts. Pregnant gilts were passively immunized with 100 ml of porcine anti-pLH (titer 1:10 000) by multiple intravenous infusions performed from 37(th) to 42(nd) day post coitum (dpc; 12-h intervals). Blood samples of pregnant gilts were taken 12 times daily from 35 until 50 dpc. Concentrations of progesterone (P(4)) and pLH were determined by radioimmunoassays in systemic blood plasma of treated gilts and control pregnant gilts. The immuno-neutralization of peripheral pLH with the use of homologous anti-pLH serum resulted in a significant reduction (p<0.001) of plasma P(4) concentrations in two out of six treated gilts only, but abortion did not occur. In the remaining four passively immunized pregnant gilts, plasma P(4) concentration was increased (p<0.001) and the abortion occurred (47 dpc) only in one of the gilts. In addition, various anti-pPAG sera were purified by sequential adsorptions with endometrial proteins of cyclic gilts. Western blotting demonstrated the expression of the PAG proteins in precipitated plasma proteins of pregnant gilts. In conclusion, the passive immuno-neutralization of porcine LH by species-homologous antiserum (anti-pLH) did not affect the pregnancy maintenance. Thus, the maintenance of mid-pregnancy in gilts may depend also on other than LH luteotrophic factors. In addition, Western analysis of precipitated plasma proteins of pregnant pigs suggests a role of the PAG family during pregnancy in the pig.
Department of Animal Physiology, University of Warmia and Mazury in Olsztyn, Poland.
Grzegorz
G
Panasiewicz
Marta
M
Majewska
Bozena
B
Szafrańska
D000818:Animals; D005260:Female; D006023:Glycoproteins / Q000502:physiology*; D007116:Immunization, Passive / Q000379:methods; D007986:Luteinizing Hormone / Q000097:blood / Q000276:immunology / Q000502:physiology*; D011247:Pregnancy; D011255:Pregnancy Maintenance / Q000502:physiology*; D011257:Pregnancy Proteins / Q000502:physiology*; D011374:Progesterone / Q000097:blood; D034421:Sus scrofa / Q000502:physiology*
D006023:Glycoproteins; D011257:Pregnancy Proteins; D011374:Progesterone; D007986:Luteinizing Hormone