The in vivo fractional rate of gingival collagen production in non-diabetic and diabetic rats. Application of a novel approach for quantification-pool expansion.

Abstract

A new approach (pool‐expansion) has been applied for quantifying the in vivo fractional rate of gingival collagen production. This approach obviates a major shortcoming inherent in a lraditional tracer approach; decreasing specific radioactivity S. R., DPM/μg proline of tissue free‐Phlproline oocurring throughout the interval during stuch production is meausured, Poolexparision, involving the injection of excess unlaheled proline concomitant with a tracer amount of nidiotabeled proline, has been judged successful for incisor gingiva of non‐diabetic control rats by the following enteria. (I) the S. R. of gingival tree‐PHlproline remained constant from 0.5 to 2 h after Phlproline anjection and (2) during this interval, radiolabeled collagen Phlhydroxyprobne S. R. inereised linearly in contrasl pool‐expansion in gingiva of diabetic rats was less successful 0.5 h after injection, the S. R. of gingival free S. R. of gingival freep‐Phlproline was less than that after 2 h. indicating incomplete pool‐expansion at 0.5 h.For meisor gingiva of non‐diabetic control rats, the fractronal rate of collagen production 1–1% a day is slouer than that in rat skin, For incisor gingiva of diaberic rats, the fractronat rate in reduced by 65%