The effect of hypoxia on plasma leptin and insulin in newborn and juvenile rats.
Hypoxia leads to a decrease in food intake and attenuated weight gain in rats. The purpose of this study was to measure plasma leptin and insulin in young rats exposed to hypoxia for 7 d as compared to a normoxic control group of the same age. One group was exposed from birth to 7 d of age; the other was exposed from 28 to 35 d of age (weaned at 21 d of age). As expected, body weight was significantly lower in rats of either age exposed to hypoxia for 7 d. Plasma leptin was significantly lower in hypoxic (2.0+/-0.2 ng/mL; n = 41) compared with normoxic (2.6+/-0.3 ng/mL; n = 30) 7-d-old rats. Plasma leptin was also significantly lower in hypoxic (1.1+/-0.1 ng/mL; n = 20) as compared to normoxic (1.5+/-0.1 ng/mL; n = 20) 35-d-old rats. Seven-day-old rats exposed to hypoxia demonstrated significant increases in plasma glucose and insulin whereas 35-d-old rats exhibited a decrease in both variables. We conclude that exposure to hypoxia for 7 d leads to a decrease in body weight and plasma leptin in infant and juvenile rats. The decrease in leptin may be an attempt to reverse hypoxia-induced anorexia.
Raff
H
H
Endocrine Research Laboratory, St. Luke's Medical Center, Milwaukee, WI 53215, USA. hraff@mcw.edu
Bruder
E D
ED
Jankowski
B M
BM
D000375:Aging / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000502:physiology; D005260:Female; D000860:Hypoxia / Q000378:metabolism* / Q000473:pathology; D007328:Insulin / Q000097:blood*; D020738:Leptin / Q000097:blood*; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley
D001786:Blood Glucose; D007328:Insulin; D020738:Leptin