title: Hypertension in response to IL-6 during pregnancy: role of AT1-receptor activation.
abstract: BACKGROUND: Increases in interleukin 6 (IL-6) and agonistic autoantibodies to the angiotensin II type 1 receptor (AT1-AA) are proposed to be important links between placental ischemia and hypertension in preeclampsia.  METHODS: The purpose of this study was to determine whether IL-6 (5 ng/day), infused into normal pregnant (NP) rats, increased mean arterial pressure (MAP) and AT1-AA. MAP was analyzed in the presence and absence of an angiotensin type 1 receptor (AT1R) antagonist, losartan, L.  RESULTS: MAP and AT1-AA increased from 102 ± 2 to 118 ± 4 mmHg and 0.7 ± 0.3 NP to 14.1 ± 1.4 chronotropic units with chronic IL-6 infusion. MAP responses to IL-6 were abolished in losartan pretreated rats (85 ± 4 in NP + L vs 85 ± 3 mmHg in IL-6 + L).  CONCLUSION: These data indicate that IL-6 stimulates AT1-AA and that activation of the AT1R mediates IL-6 induced hypertension during pregnancy.
authors.affiliation: Departments of Obstetrics and Gynecology/Physiology, Center for Excellence in Renal and Cardiovascular Research, University of Mississippi Medical Center, Jackson, MS, USA.
authors.forename: Babbette
authors.initials: B
authors.lastname: Lamarca
authors.forename: Joshua
authors.initials: J
authors.lastname: Speed
authors.forename: Lillian Fournier
authors.initials: LF
authors.lastname: Ray
authors.forename: Kathy
authors.initials: K
authors.lastname: Cockrell
authors.forename: Gerd
authors.initials: G
authors.lastname: Wallukat
authors.forename: Ralf
authors.initials: R
authors.lastname: Dechend
authors.forename: Joey
authors.initials: J
authors.lastname: Granger