Aprotinin is a bovine pancreatic trypsin inhibitor (BPTI) inhibitor which inhibits trypsin and chymotrypsin with K_is of 0.06 pM and 9 nM, respectively.

Ki: 0.06 pM (Trypsin), 9 nM (Chymotrypsin)^[1]

Aprotinin, a serine protease inhibitor isolated from bovine lung, is a complex protease inhibitor that is an antifibrinolytic, inhibits contact activation, and decreases the inflammatory response to cardiopulmonary bypass^[2]. Aprotinin inhibits trypsin (bovine, K_i= 0.06 pM), chymotrypsin (bovine, K_i= 9 nM), plasmin (human, 0.23 nM)^[1]. Aprotinin is also a competitive protein inhibitor of NOS activity. It inhibits NOS-I and NOS-II with K_i values of 50 μM and 78 μM, respectively^[3]. Aprotinin significantly inhibits fibrinolysis with an IC₅₀ of 0.16±0.05 μM^[4].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

High dose aprotinin can reduce blood loss and transfusion requirements associated with primary cardiac procedures such as coronary artery bypass graft (CABG) or heart valve replacement surgery^[5]. Aprotinin inhibits thrombus formation in a dose-dependent manner. Aprotinin at a dose of 1.5 mg kg^-1 (bolus) and 3 mg kg^-1 h^-1 infusion (maintenance infusion) causes a tendency towards a reduction in bleeding time. Aprotinin significantly reduces the bleeding time starting at a dose of 3 mg kg^-1 bolus plus 6 mg kg^-1 h^-1 showing a reduction of approximately 84%±2.9%. At the highest dose of 5 mg kg^-1 and 10 mg kg^-1 h^-1, the strongest effects are observed^[4]. Aprotinin may affect tumor necrosis factor-alpha (TNF) levels. Soluble TNFRI levels are significantly increased following I/R in the aprotinin treated wild type mice and not detected in all TNFRInull mice^[6].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

6511.44

C₂₈₄H₄₃₂N₈₄O₇₉S₇

9087-70-1

Solid

Off-white to light brown

Arg-Pro-Asp-Phe-Cys-Leu-Glu-Pro-Pro-Tyr-Thr-Gly-Pro-Cys-Lys-Ala-Arg-Ile-Ile-Arg-Tyr-Phe-Tyr-Asn-Ala-Lys-Ala-Gly-Leu-Cys-Gln-Thr-Phe-Val-Tyr-Gly-Gly-Cys-Arg-Ala-Lys-Arg-Asn-Asn-Phe-Lys-Ser-Ala-Glu-Asp-Cys-Met-Arg-Thr-Cys-Gly-Gly-Ala(Disulfide bridge: Cys5-Cys55,Cys14-Cys38,Cys30-Cys51)

RPDFCLEPPYTGPCKARIIRYFYNAKAGLCQTFVYGGCRAKRNNFKSAEDCMRTCGGA(Disulfide bridge: Cys5-Cys55,Cys14-Cys38,Cys30-Cys51)

O=C(N1[C@@H](CCC1)C(N[C@@H](CC(O)=O)C(N[C@@H](CC2=CC=CC=C2)C(N[C@@H](CSSC[C@@H](C(NCC(NCC(N[C@@H](C)C(O)=O)=O)=O)=O)NC3=O)C(N[C@@H](CC(C)C)C(N[C@@H](CCC(O)=O)C(N4[C@@H](CCC4)C(N5[C@@H](CCC5)C(N[C@@H](CC6=CC=C(C=C6)O)C(N[C@@H]([C@H](O)C)C(NCC(N7[C@@H](CCC7)C(N[C@@H](CSSC[C@@H](C(N[C@H](CCCNC(N)=N)C(N[C@@H](C)C(N[C@@H](CCCCN)C(N[C@@H](CCCNC(N)=N)C(N[C@@H](CC(N)=O)C(N[C@@H](CC(N)=O)C(N[C@@H](CC8=CC=CC=C8)C(N[C@@H](CCCCN)C(N[C@@H](CO)C(N[C@@H](C)C(N[C@@H](CCC(O)=O)C(N[C@H]9CC(O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)NC%10=O)C(N[C@@H](CCCCN)C(N[C@@H](C)C(N[C@@H](CCCNC(N)=N)C(N[C@@H]([C@@H](C)CC)C(N[C@@H]([C@@H](C)CC)C(N[C@@H](CCCNC(N)=N)C(N[C@@H](CC%11=CC=C(C=C%11)O)C(N[C@@H](CC%12=CC=CC=C%12)C(N[C@@H](CC%13=CC=C(C=C%13)O)C(N[C@@H](CC(N)=O)C(N[C@@H](C)C(N[C@@H](CCCCN)C(N[C@@H](C)C(NCC(N[C@@H](CC(C)C)C(N[C@@H](CSSC[C@@H](C(N[C@@H](CCSC)C(N[C@@H](CCCNC(N)=N)C(N[C@H]3[C@H](O)C)=O)=O)=O)NC9=O)C(N[C@@H](CCC(N)=O)C(N[C@@H]([C@H](O)C)C(N[C@@H](CC%14=CC=CC=C%14)C(N[C@@H](C(C)C)C(N[C@@H](CC%15=CC=C(C=C%15)O)C(NCC(NC%10)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)[C@H](CCCNC(N)=N)N

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

* Note: If you choose water as the stock solution, please dilute it to the working solution, then filter and sterilize it with a 0.22 μm filter before use.

• [1]. Levy JH, et al. Efficacy and safety of aprotinin in cardiac surgery. Orthopedics. 2004 Jun;27(6 Suppl):s659-62.  [Content Brief]

  [2]. Fritz H, et al. Biochemistry and applications of aprotinin, the kallikrein inhibitor from bovine organs. Arzneimittelforschung. 1983;33(4):479-94.  [Content Brief]

  [3]. Levy JH, et al. Efficacy and safety of aprotinin in cardiac surgery. Orthopedics. 2004 Jun;27(6 Suppl):s659-62.

  [4]. Venturini G, et al. Aprotinin, the first competitive protein inhibitor of NOS activity. Biochem Biophys Res Commun. 1998 Aug 10;249(1):263-5  [Content Brief]

  [5]. Sperzel M, et al. Evaluation of aprotinin and tranexamic acid in different in vitro and in vivo models of fibrinolysis, coagulation and thrombus formation. J Thromb Haemost. 2007 Oct;5(10):2113-8. Epub 2007 Jul 31.  [Content Brief]

  [6]. Davis R, et al. Aprotinin. A review of its pharmacology and therapeutic efficacy in reducing blood loss associated withcardiac surgery. Drugs. 1995 Jun;49(6):954-83.  [Content Brief]

  [7]. Sabbagh MJ, et al. Aprotinin exacerbates left ventricular dysfunction after ischemia/reperfusion in mice lacking tumor necrosis factor receptor I. J Cardiovasc Pharmacol. 2008 Oct;52(4):355-62.  [Content Brief]