Maternal and fetal stressors during development can permanently alter various
physiological functions and impact long-term health. These alterations are said to be
programmed because they persist long after the original insult. Current evidence
indicates that iron deficiency (ID) during pregnancy can induce a host of long-term
programming effects, including cardiovascular complications and behavioural deficits.
Despite the relevance of ID as a model of developmental programming, these effects
have not been extensively studied. The purpose of the present series of experiments was to develop a model of maternal ID throughout pregnancy to study its long-term
cardiovascular and behavioural consequences in neonatal and adult offspring.
Female rats were fed either a low iron diet (3 mg/kg or 10 mg/kg Fe) or a control
diet (> 225 mg/kg Fe) prior to and throughout gestation. At birth, all dams were fed a control diet (270 mg/kg Fe). This treatment caused altered growth trajectories which persisted in adulthood. Adult perinatal ID (PID) offspring, despite showing no signs of anemia at that time, had persistent elevations in arterial pressure (AP), as well as enhanced responsiveness of AP to high and low sodium intake. These animals also had altered responsiveness of renal medullary blood flow to changes in AP. PID offspring also had altered function of intrarenal and vascular nitric oxide signaling. Similar studies performed in acute ID animals revealed opposite trends in intrarenal and vascular NOS function, as well as in effects on the cardiovascular system.
In addition to the cardiovascular effects, adult PID male offspring exhibited a
number of behavioural changes, as assessed by monitoring locomotor activity in their
home cages (by radiotelemetry) as well as in a novel environment. PID male offspring
also performed poorly in a Morris water maze compared to controls. These differences
were not observed in female PID animals.
In summary, these studies provide evidence that ID during gestation has deleterious effects on various aspects of the offspring’s physiology. Given the global
incidence of ID, as well as its propensity to afflict pregnant women, developmental
programming from this condition could have profound implications on global health. / Thesis (Ph.D, Pharmacology & Toxicology) -- Queen's University, 2009-01-22 23:32:40.931
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:OKQ.1974/1669 |
| Date | 26 January 2009 |
| Creators | Bourque, STEPHANE |
| Contributors | Queen's University (Kingston, Ont.). Theses (Queen's University (Kingston, Ont.)) |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English, English |
| Detected Language | English |
| Type | Thesis |
| Format | 1272850 bytes, application/pdf |
| Rights | This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner. |
| Relation | Canadian theses |
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