Purchase this article with an account.
H. Itakura, N. Kotajima, M. Murakami, S. Kishi; The Level of C-Propeptide of Type 2 Procollagen Was Maintained in Vitreous Fluid After Vitrectomy . Invest. Ophthalmol. Vis. Sci. 2003;44(13):433.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose:Hyaluronic acid (HA) and type2 collagen are major components of the vitreous gel. The mechanism of their metabolism and regeneration are not known. To report the levels of HA and C-propeptide of type2 procollagen (CP2) in the vitreous obtained by vitrectomy and fluid-air exchange after vitrectomy. Methods:Undiluted vitreous samples about 1cc were obtained from 78 eyes of 69 patients who underwent vitrectomy for the treatment of diabetic retinopathy (DR; 48 eyes), and macular hole (MH; 30 eyes). We collected the fluid samples about 4cc obtained by fluid-air exchange after vitrectomy in 33 eyes with DR (27 eyes) and MH (6eyes). Vitreous and fluid samples were obtained from the same eyes in 16 eyes, otherwise the both vitreous and fluid samples did not match in the remaining eyes. Fluid sample was obtained one time in 12 eyes, twice in 4. Blood samples were obtained on the day before vitrectomy. Concentrations of HA and CP2 were measured by an enzyme-linked immunosorbent assay. Results:The levels of HA in the fluid samples obtained by fluid-air exchange (MH; 26.0±8.5 µg/ml , DR; 12.1±1.6 µg/ml ) were significantly lower than in the vitreous (MH; 106±10.6 µg/ml, DR; 124±11.6 µg/ml ) (p<0.001). However, no significant differences were found between CP2 levels in the fluid samples obtained by fluid-air exchange (MH; 4.9±0.7 ng/ml, DR; 5.5±0.5 ng/ml) and in the vitreous (MH; 5.0±0.3 ng/ml, DR; 6.5±0.6 ng/ml). In the same 16 eyes, HA level after vitrectomy significantly decreased (p<0.001), but CP2 level did not decrease. In the fluid obtained by the second fluid-air exchange, HA decreased compared with the first in all four eyes, but CP2 increased in two of four eyes. In the blood samples HA level was 45.3±10.5 ng/ml and CP2 level was less than 0.5 ng/ml. Conclusions:Although HA decreased in vitreous fluid after vitrectomy, CP2 was contained in fluid sample at the same level of primary vitreous sample. These results suggest that type2 procollagen is secreted into vitreous cavity even after vitrectomy.
This PDF is available to Subscribers Only