Myogenic reactivity is enhanced in rat radial uterine arteries in a model of maternal undernutrition.
OBJECTIVE
The purpose of this study was to determine if maternal undernutrition during pregnancy altered myogenic tone in small radial uterine arteries.


METHODS
Myogenic tone of radial uterine arteries was studied from late pregnant rats (day 20) that were fed either ad libitum or globally restricted diet (moderately severe dietary restriction) throughout pregnancy.


RESULTS
Myogenic tone was enhanced in the radial uterine arteries from the diet-restricted compared with the ad libitum group. Nitric oxide synthase inhibition enhanced myogenic tone in the arteries from the ad libitum group only. Prostaglandin H synthase inhibition had no effect on myogenic tone in either group.


CONCLUSIONS
Diet restriction during pregnancy enhances myogenic tone in the radial uterine arteries partly as a result of impairment of the nitric oxide synthase pathway. Enhanced myogenic tone in turn may reduce uteroplacental blood flow and, thus, contribute to reduced birth weight, and lead to effects of fetal programming in utero that can have long-term consequences into adulthood.
Perinatal Research Centre, Department of Obstetrics and Gynecology, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada.
Sukrutha
S
Veerareddy
Morag E
ME
Campbell
Sarah J
SJ
Williams
Philip N
PN
Baker
Sandra T
ST
Davidge
D000818:Animals; D001158:Arteries; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D005260:Female; D018056:Hemorheology; D044342:Malnutrition / Q000150:complications / Q000503:physiopathology*; D008469:Meclofenamic Acid / Q000494:pharmacology; D009215:Myometrium; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D021041:Placental Circulation / Q000502:physiology*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014599:Uterus / Q000098:blood supply*; D014664:Vasodilation / Q000187:drug effects
D016861:Cyclooxygenase Inhibitors; D008469:Meclofenamic Acid; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester