title: Differential effects of complement activation products c3a and c5a on cardiovascular function in hypertensive pregnant rats.
abstract: Early-onset pre-eclampsia is characterized by decreased placental perfusion, new-onset hypertension, angiogenic imbalance, and endothelial dysfunction associated with excessive activation of the innate immune complement system. Although our previous studies demonstrated that inhibition of complement activation attenuates placental ischemia-induced hypertension using the rat reduced uterine perfusion pressure (RUPP) model, the important product(s) of complement activation has yet to be identified. We hypothesized that antagonism of receptors for complement activation products C3a and C5a would improve vascular function and attenuate RUPP hypertension. On gestational day (GD) 14, rats underwent sham surgery or vascular clip placement on ovarian arteries and abdominal aorta (RUPP). Rats were treated once daily with the C5a receptor antagonist (C5aRA), PMX51 (acetyl-F-[Orn-P-(D-Cha)-WR]), the C3a receptor antagonist (C3aRA), SB290157 (N(2)-[(2,2-diphenylethoxy)acetyl]-l-arginine), or vehicle from GD 14-18. Both the C3aRA and C5aRA attenuated placental ischemia-induced hypertension without affecting the decreased fetal weight or decreased concentration of free circulating vascular endothelial growth factor (VEGF) also present in this model. The C5aRA, but not the C3aRA, attenuated placental ischemia-induced increase in heart rate and impaired endothelial-dependent relaxation. The C3aRA abrogated the acute pressor response to C3a peptide injection, but it also unexpectedly attenuated the placental ischemia-induced increase in C3a, suggesting nonreceptor-mediated effects. Overall, these results indicate that both C3a and C5a are important products of complement activation that mediate the hypertension regardless of the reduction in free plasma VEGF. The mechanism by which C3a contributes to placental ischemia-induced hypertension appears to be distinct from that of C5a, and management of pregnancy-induced hypertension is likely to require a broad anti-inflammatory approach.
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Kathryn E
authors.initials: KE
authors.lastname: Lillegard
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Alex C
authors.initials: AC
authors.lastname: Loeks-Johnson
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Opacich
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Jenna M
authors.initials: JM
authors.lastname: Peterson
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Ashley J
authors.initials: AJ
authors.lastname: Bauer
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Elmquist
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Ronald R
authors.initials: RR
authors.lastname: Regal
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota.
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Gilbert
authors.affiliation: Department of Biomedical Sciences, University of Minnesota Medical School Duluth (K.E.L., A.C.L.-J., J.W.O., J.M.P., A.J.B., B.J.E., J.S.G., J.F.R.) and Department of Mathematics and Statistics, University of Minnesota Duluth (R.R.R.), Duluth, Minnesota jregal@d.umn.edu.
authors.forename: Jean F
authors.initials: JF
authors.lastname: Regal
mesh_terms: D000818:Animals; D002319:Cardiovascular System / Q000276:immunology* / Q000503:physiopathology*; D003167:Complement Activation / Q000276:immunology*; D015926:Complement C3a / Q000037:antagonists & inhibitors / Q000276:immunology*; D015936:Complement C5a / Q000037:antagonists & inhibitors / Q000276:immunology*; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000276:immunology / Q000503:physiopathology; D005260:Female; D006339:Heart Rate / Q000276:immunology; D006973:Hypertension / Q000276:immunology* / Q000503:physiopathology*; D007511:Ischemia / Q000276:immunology / Q000503:physiopathology; D010920:Placenta / Q000276:immunology; D011247:Pregnancy; D051381:Rats; D011951:Receptors, Complement / Q000276:immunology; D042461:Vascular Endothelial Growth Factor A / Q000276:immunology
chemical_list: D011951:Receptors, Complement; D042461:Vascular Endothelial Growth Factor A; D015926:Complement C3a; D015936:Complement C5a