Quantitative analysis of collagen accumulation during protein malnutrition.

It is generally believed that protein malnutrition is detrimental to proper wound healing. However, there is limited evidence in the literature to support this. The authors studied the effect of protein depletion on the accumulation of collagen to determine the quantitative changes taking place in the healing wound. Polytetrafluoroethylene (PTFE) wound cylinders were implanted subcutaneously in 30 male Sprague-Dawley rats. The rats were divided into two groups and fed either chow (C) (n = 12) or an isocaloric protein-free (PF) diet (n = 18). Seven, 14, and 21 days later, the rats were weighed, bled, and wound cylinders harvested. PTFE cylinder collagen content, hematologic parameters, total serum protein, and serum albumin were determined. The rats with the PF diet had significant (P < .001) weight loss at all time-points (day 7, PF = 176.2 +/- 3.2, F = 252.4 +/- 3.8; day 14, PF = 154.8 +/- 3.6, F = 289.3 +/- 9.2; day 21, PF = 150.8 +/- 3.9, F = 307.6 +/- 12.2). Total serum protein was also depleted as compared with controls (P < .001). White blood cell counts were significantly higher on day 7 (PF = 7.5 +/- 0.9, C = 4.4 +/- 0.9, P < .03) in the PF group; however, this was not sustained, and there was no difference between the groups on days 14 and 21. Collagen content (micrograms of 5-hydroxyproline [OHP] per centimeter PTFE) was diminished on day 7 (PF = 12.7 +/- 2.0, C = 24.7 +/- 3.4, P < .03). No difference was seen on day 14.(ABSTRACT TRUNCATED AT 250 WORDS)