Abstract
Selected antihaemostatic parameters associated with the bite of the Asian medicinal leechHirudo nipponia were investigated in human volunteers. This study confirms earlier work onHirudo medicinalis, in that the wound from a leech bite bleeds for hours even though blood coagulates normally after about 15 min. The whole blood clotting time forH. nipponia after 1 min was 12.88±3.15 min, comparable to that forH. medicinalis, but in both cases clotting time returned to control levels after about 15 min. However, the duration of bleeding from the bite ofH. nipponia (mean=210 min) was consistently shorter thanH. medicinalis, even when adjusted for size differences (mean=490 min). Similarly, the blood flow rate fromH. nipponia (mean-39 μl/min) is markedly slower thanH. medicinalis (mean =200 μl/min). The total blood lost from the host, therefore, was approximately ten times more withH. medicinalis thanH. nipponia. Collagen-induced platelet aggregation was significantly impaired in blood from theH. nipponia bite wound in 25 min. This may indicate that the prolongation of bleeding is caused by inhibition of platelet aggregation rather than by thrombin inhibition alone.
In both species, the saliva of the leech contains a potent antithrombin whose inhibitory activity returns to normal levels approximately 15 min after cessation of feeding. The internal amino acid sequence of the thrombin inhibitor secreted byH. nipponia into the saliva is unexpectedly different (55%) from that of hirudin secreted byH. medicinalis. This difference in sequence is reflected in the lack of neutralisation by the polyclonal antibody to hurudin fromH. medicinalis. Blockage of the N-terminal in antithrombin fromH. nipponia appears to be a further real difference compared to hirudin fromH. medicinalis.
The biological significance, if any, of these differences between species in bleeding time and antithrombin structure remains an open, but intriguing, question.
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References
Deckman H, Stassen JM, Vreys I et al. (1995) Calin fromHirudo medicinalis, an inhibitor of platelet adhesion to collagen, prevents platelet-rich thrombosis in hamsters. Blood 85:712–719
Dodt J (1995) Anticoagulatory substances of bloodsucking animals: from hirudin to hirudin mimetics. Anges Chem Int Ed Engl 34:867–880
Groetsch H, Damm D, Youssef RB et al. (1991) Comparison of two different methods for the determination of rDNA-hirudin in plasma samples: HPLC vs a chromogenic thrombin substrate. Thromb Res 64:273–277
Hong SJ, Kim DR, Jung HI et al. (1993) The leech as a laboratory animal for the biomedical research. Korean J Zool 36:588–595
Keegan HL, Toshioka S, Suzuki H (1968) Blood-sucking Asian leeches of families Hirudidae and Haemadipsidae. 406th Med Lab Spec Report, July 1968. US Army Medical Command, Japan
Markwardt F, Stüzebecher J, Walsmann P (1990) The hirudin standard. Thromb Res 59:395–400
Munro R, Hechtel FOP, Sawyer RT (1989) Sustained bleeding after a leech bite in the apparent absence of hirudin. Throm Haemost 61:366–369
Munro R, Powell J, Sawyer RT (1991a) Calin-a platelet adhesion inhibitor from the saliva of the medicinal leech. Blood Coag Fibrinol 2:179–184
Munro R, Siddall M, Desser SS et al. (1991b) Bleeding in human volunteers from the bite of the American medicinal leechMacrobdella decora compared with its European counterpartHirudo medicinalis. Comp Haematol Int 1:214–216
Munro R, Sawyer RT, Hechtel FOP et al. (1992) Sustained bleeding from bites of hatchling leeches. Comp Haematol Int 2:27–29
Yun-Choi HS, Kim SO, Kim JH et al. (1995) Modified smear method for screening potential inhibitors of platelet aggregation from plant sources. J Nat Prod 48:363–370
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Hong, S.J., Sawyer, R.T. & Kang, K.W. Prolonged bleeding from the bite of the Asian medicinal leechHirudo nipponia . Comp Haematol Int 9, 125–131 (1999). https://doi.org/10.1007/BF02600370
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DOI: https://doi.org/10.1007/BF02600370