Changes in protein distribution in the rat during prolonged "systemic injury".
A model of prolonged systemic injury was generated in the rat by three sequential injections of turpentine, delivered at 2-day intervals. The model was then used to identify the subsequent changes in the distribution of tissue protein and the effects of the changes in skin protein on the tensile strength of healing skin wounds. The model produced a sustained acute phase response during the 6 days of the study, including a significant (26%) reduction in the plasma glutamine concentration (P < 0.01), which was not achieved with a single injection of turpentine. When compared with pair-fed controls, the animals injected with turpentine had 18% more nitrogen in the liver (P < 0.05), 25% less in the gastrocnemius muscle (P < 0.01), and a similar amount in the upper small intestine. There was also a 30% loss of nitrogen from dorsal skin (P < 0.001) and a 15% loss from ventral skin (P < 0.01), with a parallel loss of collagen (measured as hydroxyproline). Ten days after the first injection of turpentine, the dorsal skin was still 18% thinner than that of the pair-fed controls (P < 0.01): this was associated with an 18% reduction in the bursting strength of linear skin wounds (P < 0.05). Such changes were not observed in pair-fed controls. These studies demonstrate that systemic injury (independent of dietary intake) causes a preferential loss of protein from peripheral tissues (skin, muscle) and preservation of protein in splanchnic tissue (liver, intestine). They also suggest that the loss of skin protein including collagen is quantitatively important, with functional consequences in reducing the bursting strength of surgical skin wounds.
Wusteman
M
M
MRC Dunn Nutrition Unit, Cambridge, United Kingdom.
Hayes
A
A
Stirling
D
D
Elia
M
M
D000210:Acute-Phase Reaction / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D001769:Blood / Q000378:metabolism; D001835:Body Weight; D003094:Collagen / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D009929:Organ Size; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012867:Skin / Q000378:metabolism / Q000473:pathology; D013997:Time Factors; D014018:Tissue Distribution; D014425:Turpentine / Q000008:administration & dosage
D011506:Proteins; D005973:Glutamine; D003094:Collagen; D009584:Nitrogen; D014425:Turpentine