[The concentration of cerebral natriuretic peptide in tear and blood serum.]

The natriuretic peptides regulate pressure and water metabolism in human organism. The concentration of N-thermal cerebral natriuretic propeptide (NT-proBNP) in tear and blood serum was analyzed. The sampling included 49 patients divided on three groups. The group I (main) included 14 patients with primary open-angle sub-compensated glaucoma degree I-III. The group II (comparative group) included 15 patients with age-related immature cataract. The group III (control) included volunteers without any visual organ diseases. The concentration of NT-proBNP in tear and blood serum was detected by solid-phase enzyme-linked immunosorbent assay technique using test system NT-proBNP - IFA - BEST» («Vektor-Best», Russia). The median of content of NT-proBNP in tear turned out to be less than in blood serum in all groups (р1 = 0,00763; р2 = 0,00452; р3 = 0,00029) and made up to in patients with glaucoma 41,3 pg/ml, with cataract - 37.5 pg/ml, in healthy people 0 25.0 pg/ml (inter-quartile range made up to 20-60 pg/ml, 20-65 pg/ml, 10-49,5 pg/ml correspondingly). No differences in concentration of NT-proBNP were established in all groups both for blood serum (p = 0,494) and tear (p = 0,388). The concentration of NT-proBNP in tear correlated with its concentration in blood serum (r = 0,694). However, no dependencies were established from value of intra-ocular pressure (r = 0,168). Therefore, the concentration of NTproBNP in tear is not a perspective laboratory arker for diagnostic of increased intra-ocular pressure and stratification of development of glaucoma.