Determination of hydroxyproline in liver.

THE DETERMINATION of hydroxyproline in parenchymous tissues such as liver presents special problems not encountered in collagenons tissues. This is true because liver contains only small quantities of this imino acid (1), and furthermore, the existing quantitative tests are nonspecific. Thus, if one were to use the usually acceptable Neuman and Logan procedure (2), a separate determination for tyrosine would have to be made to correct for its contributing interference in the color production (2). Since this contribution is of the same order of magnitude as that of hydroxyproline in liver (3), the method loses its quantitative aspects. This paper describes a procedure wherein tyrosine is preferentially adsorbed allowing hydroxyproline to be quantitatively determined.