Effect of intrauterine growth restriction on blood pressure, glucose tolerance and sympathetic nervous system activity in the rat at 3-4 months of age.
OBJECTIVE
Epidemiological studies suggest that intrauterine growth restriction (IUGR) due to maternal undernutrition during pregnancy represents a major risk factor for hypertension and diabetes in adult age. However, placental insufficiency, rather than maternal malnutrition, is the main cause of IUGR in the Western world. We therefore studied the relationship between birth weight and adult blood pressure and glucose tolerance in an established animal model of placental insufficiency.


METHODS
IUGR was induced by uterine artery ligation in pregnant rats and the offspring were studied at 3-4 months of age.


METHODS
In one subgroup of animals (n = 41, birth weight range 3.2-6.6 g) blood pressure was recorded over 72 h using telemetry and hypothalamic tissue levels of noradrenaline was measured. In another subgroup (n = 30, birth weight range 3.0-6.8 g) the activity of the sympathetic nervous system (SNS) was assessed by noradrenaline isotope dilution techniques and glucose tolerance determined by an intravenous glucose load.


RESULTS
Adult blood pressure was independent of birth weight Haemodynamic responses of IUGR rats to moderate sound stress was unaltered. In male rats neither SNS activity, hypothalamic noradrenaline concentrations nor glucose tolerance was associated with birth weight In contrast, IUGR in female rats was associated with increased SNS activity, elevated fasting blood glucose as well as lower insulin and higher glucose levels in response to a glucose load.


CONCLUSIONS
IUGR is not linked to an elevated blood pressure at 3-4 months of age in this model. However, in female rats, IUGR is associated with increased SNS activity and impaired glucose tolerance in adult life.
Jansson
T
T
Perinatal Center, Department of Physiology and Pharmacology, Göteborg University, Sweden. thomas.jansson@fysiologi.gu.se
Lambert
G W
GW
D000818:Animals; D019540:Area Under Curve; D001724:Birth Weight / Q000502:physiology; D001786:Blood Glucose; D001794:Blood Pressure / Q000502:physiology*; D002395:Catecholamines / Q000378:metabolism; D002940:Circadian Rhythm; D004195:Disease Models, Animal; D005260:Female; D005317:Fetal Growth Retardation / Q000503:physiopathology*; D005951:Glucose Tolerance Test; D006339:Heart Rate; D007031:Hypothalamus / Q000378:metabolism; D007328:Insulin / Q000097:blood; D008297:Male; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D012737:Sex Factors; D013564:Sympathetic Nervous System / Q000502:physiology*
D001786:Blood Glucose; D002395:Catecholamines; D007328:Insulin