RT Journal Article
SR Electronic
T1 THE INHIBITION OF NOREPINEPHRINE-STIMULATED LIPOLYSIS BY ACUTE HYPOXIA
JF Journal of Pharmacology and Experimental Therapeutics
JO J Pharmacol Exp Ther
FD American Society for Pharmacology and Experimental Therapeutics
SP 87
OP 94
VO 169
IS 1
A1 BAUM, DAVID
YR 1969
UL http://jpet.aspetjournals.org/content/169/1/87.abstract
AB The effect of acute hypoxia upon norepinephrine-stimulated lipolysis was investigated in puppies. Twenty-two animals were given norepinephrine (0.4 µg/kg/min) for 120 minutes. After 45 minutes of norepinephrine infusion and ventilation with air, plasma glycerol rose to 348 ± 19% and free fatty acids to 305 ± 29% mean control (mean ± S.E.). In five puppies continued on air (arterial pO2,>75 mm Hg) and seven puppies given 13% oxygen-87% nitrogen (arterial pO2 , 36-57 mm Hg) for 45 minutes and returned to air, plasma glycerol and free fatty acid levels declined slowly, although they remained elevated throughout the norepinephrine infusion. In contrast, in five other animals ventilated with 8% oxygen-92% nitrogen (arterial pO2, 19-31 mm Hg) for 45 minutes, plasma glycerol and free fatty acids fell precipitously to near prenorepinephrine levels. During norepinephrine administration to animals ventilated with 8% oxygen-92% nitrogen, a significant negative correlation was found between plasma lactate and free fatty acids and between plasma lactate and glycerol. In the five remaining animals, L-lactate infusion replaced the period of hypoxia, resulting in large falls in plasma glycerol and free fatty acids. These observations indicate that norepinephrine-stimulated lipolysis is markedly inhibited by severe hypoxia and suggest that reduced mobilization contributes to the loss of free fatty acids as a fuel source in the severely hypoxic puppy. Furthermore, they imply that anaerobic glycolysis needs to be considered as a factor in impaired lipolysis during severe hypoxia. © 1969, by The Williams & Wilkins Company