Tissue hydroxyproline assay

It is the purpose of this review to outline critically the methods available for hydroxyproline assay, and to summarize the information obtained by hydroxyproline determinations in urine, plasma (or serum), and the tissues, with emphasis on understanding the physiological and pathological setting in which these measurements have been made. No attempt will be made to discuss recent developments in the chemistry (H3, H4) or the biosynthesis (Ul) of collagen, since thorough reviews of these topics are available. 

L12. LeRoy, E. C., Harris, E. D., and Sjoerdsma, A., A modified procedure for radioactive hydroxyproline assay in urine and tissues after labeled proline administration. Anal. Biochem. 17, 377-382 (1966). 

Since the presence of hydroxyprohne is unique in collagen elastin contains a small amount), the determination of collagen content in a coUagen-rich tissue is readily done by assaying the hydroxyproline content. 

When Severo Ochoa left the Biochemistry Department at New York University I had to search for another mentor and I was fortunate to be able to continue my graduate work with Albert Keston. While developing the isotope derivative method for amino acid assay we showed for the first time that hydroxyproline was uniquely present in collagen. This observation made a great impression on me. Furthermore, I had the good fortune while at New York University Medical School to meet and to get to know the late Joseph Bunim. It was from him that I learned about the role of collagen in connective tissue and also about collagen diseases. 

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