Beef lung

Most of the common methods of isolation of heparin (described in sufficient detail in monographs128-30) are based on a procedure, developed by Charles and Scott,31 involving autolysis of the tissue (originally beef liver and beef lung), extraction with alkali, coagulation of proteins by heating, and precipitation of a heparin - protein complex by acidification. Heparin is recovered from the complex by reprecipitation with ethanol, or acetone, or both. Fats are removed by extraction with ethanol, and proteins by treatment with trypsin. Modifications of this proce-... 

Sulfur analysis provides a useful criterion of purity for heparins. As shown in Table II, heparins from different sources have sulfate-to-car-boxyl molar ratios of 1.9-2.55 1.00, the highest values being from beef-lung preparations. 

BL = beef lung SM = sheep-intestinal mucosa PD = pig duodenum PM = pig-intestinal mucosa. 8 Residues per disaccharide unit.c Lipoproteinlipase-inducing units. Fractions from PM I. 

The amino sugar counterparts of D-glucuronic acid and nonsulfated L-iduronic acid in heparin are either N-acetylated, or nonsulfated at C-6, or both. 2-Acetamido-2-deoxy-D-glucosyl residues account for only a minor proportion of the total hexosamine in heparin, and are especially low in beef-lung preparations (see Table II).8,138,147 -149 In contrast, they... 

Fig. 9. — (a) H-N.m.r. Spectrum (270 MHz, Resolution-enhanced) of Beef-lung Heparin in D20 (40%, w/v) at 90° (b) Computer-simulated Spectrum, with Calculated, Interproton Coupling-Constants (/, at 35°) for the Amino Sugar (A) and L-Iduronic acid (I) Residues.84... 

Howell88 considered it to be a derivative of D-glucuronic acid, but this view was not confirmed by Charles and Scott,89 who isolated a crystalline barium heparinate from beef lung and detected the presence in it of an amino sugar. 

D-Galactose H HO HO H HOH2 C—C—C—C—C—CHO HO H H HO widespread in plants lactose ovomucoid cerebrosides albumin gland of snail frog and toad spawn beef lung... 

Heparin Glycosaminoglycan Beef lung, pig gastric mucosa 3 000-40 000... 

Heparin was originally extracted from liver (hence its name), but commercial preparations are now obtained by extraction from beef lung or porcine gastric mucosa. 

Heparin is a glycosaminoglycan extracted from animal tissues (porcine mucosa, beef lung, etc.). It is a mixture of molecules having a mean molecular weight of 15,000 Da. A pentasaccharide sequence found in approximately one third of the molecules binds to antithrombin in mammalian blood, enhancing its inhibitory effects on the enzymes thrombin, factor Xa, factor Vila, and factor IXa. The reaction is reversible, heparin being released after the antithrombin molecule binds to the procoagulant enzymes. Heparin binds to platelets, platelet factor-4 (which neutralizes it), histidine-rich GP vWp and a number of other proteins. Its half-life is about one hour in the circulation (18). Antibodies to heparin... 

Charles and Scott employed the cheaper and more readily available beef liver and beef lung as the source material. 

The unfiactionated heparin is primarily used as an anticoagulant for both the therapeutic and surgical indications. Usu ly beef lung and porcine mucosal derived products are available for these indications. The unfiactionated hepatitis have been recently used for the following additional tiierapeutic uses ... 

Unfractionated Heparin Yes Low-Molecular-Weight Heparins (LMWHs) Extracted from porcine gut mucosa or beef lung f 15,000 30-90 min (dose dependent) 1 1 SC 30-70% (dose dependent)... 

Figure 4. Anticoagulant activity of individual heparin chains of beef-lung heparin. Chains were separated by electrophoresis of Upjohn beef-lung heparin Lot 517-042 with LKB carrier ampholine batch 18. The apparent molecular weights were obtained from electrophoresis in acrylamide by the technique of Hilborn and Anastassiadis (10). The anticoagulant activity was determined by the USP procedure comparing the individual fraction with the original heparin. The quantity was estimated by optical density of toluidine blue-stained band on gel. (2)...

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