Hormones 



Insulin 



The myriad chemical processes taking place in fish, as in mammals, 

 are subject to control and integration by means of specific chenical 

 substances known as hormones. These substances are secreted by the en- 

 docrine glands into the blood stream and are distributed throughout the 

 body, serving to maintain a proper balance of the various body functions. 



With certain exceptions, most hormone therapy remains in the experi- 

 mental stages. Insulin, a pancreatic hormone, controls carbohydrate 

 metabolism in the body and has found very large scale use in the treatment 

 of diabetes. In recent years, the incidence of this disease in older 

 people has increased and the demand for insulin has increased accord- 

 ingly. At present, beef pancreas is the main source of insulin, the hor- 

 mone being extracted by dilute acid alcohol, after which it is precipi- 

 tated, purified, and modified i^en so desired as a zinc or protamine com- 

 plex for clinical use. However, the total available supply of beef pan- 

 creas is limited and competition exists between insulin and enzyme manu- 

 facturers for its procurement. 



Possibility of Utilizing Salmon Cannery Waste as a Source of Insulin 



The producers of insulin have made several attempts to extract fish 

 insulin and have met with some degree of success. They have found that 

 codfish pancreas is a good source, yielding several times as much insulin 

 as an equivalent simount of beef pancreas. However, the raw material cost 

 was too great due to the large amount of liand labor involved in obtaining 

 sufficient quantities of the minute organs. 



Unfortunately, the preparation of insulin from the waste salmon pancreas 

 would present even greater difficulties. Instead of being a single small 

 organ, the salmon pancreas is a diffuse tissue spread along the outside 

 of the intestinal tract from the lower part of the stomach to the in- 

 testine. The pancreatic cells within this tissue are difficult to recognize 

 and their separation in the voliime necessary for commercial production of 

 insulin would be uneconomical. It is possible, however, that a method 

 of isolation could be worked out utilizing the entire section of the di- 

 gestive tract stripped of the pyloric ceca. This section would either have 

 to be used fresh or would have to be frozen and held in cold storage in 

 order to attain the maximum yield when subsequently processed. Consider- 

 ing the fact that preliminary explorations in producing insulin from salmon 

 are yet to be made, and in view of the many obvious difficulties that would 

 be encountered due to the nature of the material, it becomes apparent 

 that the possibility of utilization of salmon waste for insulin production 

 at the present time is entirely unfeasible. 



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