In vivo 31P-NMR studies of age and energy metabolism in an animal flap model.
Changes in phosphate energy metabolism with time in a rat flap model were followed noninvasively with in vivo 31P-NMR. The influence of age on high-energy phosphate metabolites in perfused and ischemic ends of 3 x 10 cm dorsal flaps was noted from 30 minutes to 7 days after closure in 6-, 12-, and 24-month-old (n = 4, 7, and 8, respectively) male Fischer 344 rats. Phosphocreatine to inorganic phosphate ratios showed younger animals exhibiting significant returns to preinjury energy status in 2- and 3-mm ischemic layers. This behavior, 24 to 72 hours after closure, coincides with neovascularization of the flap tissue. By contrast, 12- and 24-month-old animals experienced statistically significantly lesser high-energy rebound, developing greater necrosis in the ischemic regions. Early intracellular pH lowering, indicative of lactate production, was somewhat greater in the flaps of younger animals. The in vivo 31P-NMR methods thus provide metabolic insights into flap behavior correlating with physiologic influences of aging.
Schweizer
M P
MP
Department of Medicinal Chemistry, University of Utah, Salt Lake City, USA.
Sylvester
J
J
Chick
L R
LR
Tang
P P
PP
D000375:Aging / Q000502:physiology*; D000818:Animals; D004734:Energy Metabolism / Q000502:physiology*; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009336:Necrosis; D010758:Phosphorus; D051381:Rats; D011916:Rats, Inbred F344; D012867:Skin / Q000378:metabolism* / Q000473:pathology; D013524:Surgical Flaps / Q000473:pathology / Q000502:physiology*
D010758:Phosphorus