A COMPARATIVE PHYSICAL 



AND CHEMICAL CHARACTERISTICS 



OF PRECOLLAGEN AND COLLASTROMINE 



A. A. TUSTANOVSKY 



The State Institute of Rheumatism 

 of the Ministry of Health, Moscow, RSFSR 



According to our pertinent data the collagen (the primary collagen fibril) 

 of mature connective tissue is considered as a product of precollagen 

 and collastromine combination. At the initial stages of both embryonic 

 development and formation of connective tissue only the fibers of precolla- 

 gen are formed. The participation of procollagen at this stage has not been 

 proved as yet. The properties of precollagen and collastromine studied 

 so far are practically identical. The precollagen fibers of pig's embryonic 

 skin were isolated as préparations. It was established that thèse fibers 

 are closely related with the nuclei of mesenchymal cells. Histochemical, 

 chemical, electronmicroscopical and X-ray structural analyses confirmed 

 that precollagen is an embryonic form of collastromine. 



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