Abstract
Not only patients with diabetes mellitus but also patients with renal failure had high hemoglobin A1 (HbA1) levels.
The high performance liquid chromatographic quantification of components of the HbA1 showed that the fractional pattern of HbA1 in patients with renal failure was similar to that seen in normal subjects rather than in diabetic patients.
In diabetic patients, there was a positive correlation between HbA1 values obtained by the column method and those obtained by the thiobarbituric acid (TBA) method. However, although patients with renal failure had high HbA1 levels, the patients showed HbA1 levels similar to those observed in normal subjects, according to the TBA method.
Then, the formation of HbA1 based on incubation of red blood cells with urea and other substances was observed. It was revealed that HbA1 in patients with renal failure could be formed by Hb and cyanic acid originated from urea.
In addition, as non-enzymatic glycosylation may be a generalized reaction, we utilized the reaction in which glucose is linked to the amino group of Hb and obtained the result, that glucose could attach to the amino group of 3, 5, 3'-L-triiodothyronine (T3), a thyroid hormone. Moreover, we also demonstrated that glycosylated T3 could be separated from T3 by high performance liquid chromatography.
The non-enzymatic binding reaction between various amino acids and glucose as observed in the present study seem to be a common reaction in the living body.
