On pancreatic lipase. III. The separation of lipase from its co-enzyme / by O. Rosenheim.

  • Rosenheim, Otto, 1871-1955.
Date:
1910
Catalogue details

Licence: In copyright

Credit: On pancreatic lipase. III. The separation of lipase from its co-enzyme / by O. Rosenheim. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    ! Many experiments have sho >if the activity of the mixture of inactive lipase and co-enzyme i at as that of the original pan- creatic extract and it can be demonstrated by using as little as 5 mg. o the dry powder mentioned above. With regard to the chemical nature of the co-enzyme it may be stated that it dialyses readily, is thermo-stable and seems to be soluble in dilute, but not in absolute alcohol and insoluble in ether. Its activity is lost on incineration of the active dialysate. This separation of lipase into co-enzyme and inactive lipase makes it possible to analyse the action of bile salts. The results of experiments, which will be communicated later, showed that sodium cholalate had no action on the co-enzyme, but possesses a powerful activating action on the insoluble lipase, in the course of which the latter is rendered soluble. The supposed activating effect of lecithin (and kephalin) was not confirmed, but it was found that one of the cleavage products of lecithin, namely glycero- phosphoric acid (as a sodium salt), induces a remarkable activation. Choline as hydro- chloride or as the free base, cannot act as an activator, but brings the insoluble lipase into solution, a fact which will be further examined in connection with the state of inactive lipase in pancreatic juice. Acids and alkalis were found to be inactive. The effect of serum on pancreatic lipase, recorded in the preceding communication, made it desirable to investigate its action on inactive lipase. Both normal animal and human sera were found to activate the inactive lipase to a remarkable degree. Their effect is shown in the following table. Th‘e inactive lipase was used as a fine emulsion in water (1 c.c. containing 10 mgs.); 5 c.c. olive oil emulsion were used in each case. C.C. jy KOH required Inactive Lipase (10 mgs.)+ 6 c.c. Water 0-9 Co-enzyme Solution (5 c.c.) +1 c.c. Water 0-9 Inactive Lipase + Co-enzyme +1 c.c. Water 20-2 Inactive Lipase + 1 c.c. Human serum+5 c.c. Water 29-2 Inactive Lipase + 1 c.c. Dog’s serum+ 5 c.c. Water 31-4 It will be seen that the activation by the serum is greater than that induced by the amount of co-enzyme used in this case. It was found that serum also activates the inactive lipoclastic enzyme of fresh pancreatic juice of the dog as obtained by the injection of secretin. I’ancrcatic Olive oil N juice Kmulsion Water Scrum c.c. jq KOU required 1 C.C. 5 C.C. — 0-2 1 C.C. 5 c.c. 5 c.c. — 20 1 C.C.