OBJECTIVE: A central component of preeclampsia is a reduction in utero-placental perfusion. We tested the hypothesis that vascular reactivity of second - order mesenteric arteries would be increased in a pregnant rat with reduced uterine perfusion pressure (RUPP). METHODS: Pregnant 10-12 week old Sprague-Dawley rats underwent RUPP surgery on gestational day 14, and experiments were carried out on day 20. SHAM operated animals were used as controls. Resistance caliber mesenteric arteries (200-250 μm) were isolated, myogenic reactivity and responses to vasoconstrictor and vasodilator agonists were assessed utilizing a pressurized arteriograph system. RESULTS: RUPP resulted in maternal hypertension and reductions in fetal number and weight. Resistance caliber mesenteric arteries (200-250 μm) were isolated, myogenic reactivity and responses to vasoconstrictor and vasodilator agonists were assessed utilizing a pressurized arteriograph system. Myogenic reactivity responses were normalized as a percent change in vessel diameter from an initial diameter at 20 mmHg. The mesenteric arteries from RUPP animals exhibited a significant increase in myogenic reactivity compared to SHAM controls (p < 0.05). This increased myogenicity was reversed with prostaglandin inhibition, suggesting a role for a vasoconstrictor prostaglandin. In addition to alterations in myogenic reactivity, resistance-sized arteries from RUPP animals have decreased responses to nitric oxide (NO) as evidenced by decreases in responses to methacholine (ME; P < 0.05) and no change in myogenic reactivity after NO synthase blockade. CONCLUSION: RUPP alters the behavior of resistance caliber arteries to favor a more contractile phenotype with decreased in NO responses, which is similar to what is seen in preeclampsia.
OBJECTIVE: A central component of preeclampsia is a reduction in utero-placental perfusion. We tested the hypothesis that vascular reactivity of second - order mesenteric arteries would be increased in a pregnant rat with reduced uterine perfusion pressure (RUPP). METHODS: Pregnant 10-12 week old Sprague-Dawley rats underwent RUPP surgery on gestational day 14, and experiments were carried out on day 20. SHAM operated animals were used as controls. Resistance caliber mesenteric arteries (200-250 μm) were isolated, myogenic reactivity and responses to vasoconstrictor and vasodilator agonists were assessed utilizing a pressurized arteriograph system. RESULTS: RUPP resulted in maternal hypertension and reductions in fetal number and weight. Resistance caliber mesenteric arteries (200-250 μm) were isolated, myogenic reactivity and responses to vasoconstrictor and vasodilator agonists were assessed utilizing a pressurized arteriograph system. Myogenic reactivity responses were normalized as a percent change in vessel diameter from an initial diameter at 20 mmHg. The mesenteric arteries from RUPP animals exhibited a significant increase in myogenic reactivity compared to SHAM controls (p < 0.05). This increased myogenicity was reversed with prostaglandin inhibition, suggesting a role for a vasoconstrictor prostaglandin. In addition to alterations in myogenic reactivity, resistance-sized arteries from RUPP animals have decreased responses to nitric oxide (NO) as evidenced by decreases in responses to methacholine (ME; P < 0.05) and no change in myogenic reactivity after NO synthase blockade. CONCLUSION: RUPP alters the behavior of resistance caliber arteries to favor a more contractile phenotype with decreased in NO responses, which is similar to what is seen in preeclampsia.
Authors: John J Reho; Jonathan D Toot; Jennifer Peck; Jacqueline Novak; Yang H Yun; Rolando J Ramirez Journal: Pregnancy Hypertens Date: 2011-12-13 Impact factor: 2.899
Authors: J S Morton; J Levasseur; E Ganguly; A Quon; R Kirschenman; J R B Dyck; G M Fraser; S T Davidge Journal: Sci Rep Date: 2019-07-02 Impact factor: 4.379
Authors: Joanna L Stanley; Karolina Sulek; Irene J Andersson; Sandra T Davidge; Louise C Kenny; Colin P Sibley; Rupasri Mandal; David S Wishart; David I Broadhurst; Philip N Baker Journal: Sci Rep Date: 2015-12-15 Impact factor: 4.379