Brazilian Journal of Anesthesiology
https://bjan-sba.org/article/doi/10.1016/j.bjan.2012.09.006
Brazilian Journal of Anesthesiology
Scientific Article

Efeito in vitro de dexmedetomidina na agregação plaquetária

In vitro effect of dexmedetomidine on platelet aggregation

Emine Arzu Kose; Oral Nevruz; Mehtap Honca; Vedat Yildirim

http://dx.doi.org/10.1016/j.bjan.2012.09.006 Braz J Anesthesiol, vol.63, n5, p.415-418, 2013
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Resumo

JUSTIFICATIVA E OBJETIVOS: Dexmedetomidina é um α2-agonista seletivo. Há 250-300 receptores α2-adrenérgicos na superfície de cada uma das plaquetas humanas e a efedrina induz a agregação das plaquetas por ligação desses receptores. Este estudo foi desenvolvido para estudar a função plaquetária após incubação com concentrações terapêuticas de dexmedetomidina. MÉTODOS: O estudo foi conduzido com 18 homens saudáveis, não fumantes, com idades entre 25 e 35 anos. Porque o intervalo recomendado de concentração terapêutica de dexmedetomidina, obtido por infusão intravenosa, é de 0,4-1,2 ng.mL-1, as soluções de dexmedetomidina foram preparadas em três concentrações diferentes. Os valores calculados da solução de dexmedetomidina e do diluente sem dexmedetomidina (controle) foram adicionados a uma amostra de sangue. Assim, 0; 0,4; 0,8 e 1,2 ng.mL-1 de concentrações plasmáticas de dexmedetomidina foram obtidas. Cada concentração de dexmedetomidina foi incubada com sangue total a 37ºC durante 15 minutos. Em seguida, as amostras de sangue foram centrifugadas para preparar o plasma rico em plaquetas e o plasma pobre em plaquetas. O plasma rico em plaquetas foi diluído com o plasma pobre em plaquetas para gerar o teste de plasma rico em plaquetas com uma contagem final de plaquetas de 250 ± 50 x 10(9).L-1. RESULTADOS: As amplitudes e os declives da agregação plaquetária foram estatisticamente semelhantes entre todos os grupos nos testes de agregação feitos com ADP, colágeno ou adrenalina. CONCLUSÃO:As concentrações terapêuticas de dexmedetomidina não tiveram efeito in vitro nas funções plaquetárias de indivíduos saudáveis.

Palavras-chave

ANALGÉSICOS, Dexmedetomidina, Agregação Plaquetária, In Vitro

Abstract

BACKGROUND AND OBJECTIVES: Dexmedetomidine is a selective α2-agonist. There are 250-300 α2-adrenoceptor on the surface of each human platelet and ephedrine induces platelet aggregation by binding these receptors. This study was designed to study platelet function after incubation with therapeutic concentrations of dexmedetomidine. METHODS: The study was carried out on 18 healthy, non-smoking males, ages ranging 25 to 35 years old. Because of the recommended therapeutic concentration range of dexmedetomidine obtained by intravenous infusion is 0.4-1.2 ng.mL-1, dexmedetomidine solutions were prepared in three different concentrations. The calculated value of dexmedetomidine solution and diluent without dexmedetomidine as control were added to the blood sample. Thus, we obtained 0, 0.4, 0.8 and 1.2 ng.mL-1 dexmedetomidine concentrations of plasma. Each concentration of dexmedetomidine was incubated with whole blood at 37ºC during 15 minutes. Then blood samples were centrifugated to prepare platelet-rich plasma and platelet-poor plasma. The platelet-rich plasma was diluted with the platelet-poor plasma to yield test platelet-rich plasma with a final platelet count of 250 ± 50 X 10(9).L-1. RESULTS: The platelet aggregation amplitudes and slopes were statistically similar among all groups by the aggregation test, which were performed with ADP, collagen or epinephrine. CONCLUSION: Therapeutic concentrations of dexmedetomidine had no effect on the platelet functions in healthy individuals in vitro.

Keywords

Dexmedetomidine, In Vitro, Platelet aggregation

References

Maze M, Tranquilli W. Alpha-2 adrenoceptor agonists: Defining the role in clinical anesthesia. Anesthesiology. 1991;74:581-605.

Afonso J, Reis F. Dexmedetomidine: current role in anesthesia and intensive care. Rev Bras Anestesiol. 2012;62:118-133.

Bhana N, Goa KL, McClellan KJ. Dexmedetomidine. Drugs. 2000;59:263-268.

Ozkose Z, Demir FS, Panpal K. Hemodynamic and anesthetic advantages of dexmedetomidine, an α2-agonist, for surgery in prone position. Thaku J Exp Med. 2006;210:153-160.

Kerry R, Scrutton MC, Wallis RB. Mammalian platelet adrenoceptors. Br J Pharmac. 1984;81:91-102.

Ardlie NG, McGuiness JA, Garret JJ. Effect on human platelets of catecholamines at levels achieved in the circulation. Atherosclerosis. 1985;58:251-259.

Kottke-Marchant K, Corcoran G. The laboratory diagnosis of platelet disorders: an algorithmic approach. Arch Pathol Lab Med. 2002;126:133-146.

Hjendahl P, Chronos NAF, Wilson DJ. Epinephrine sensitizes human platelets in vivo and in vitro as studied by fibrinogen binding and selectin expression. Arterioscler Thromb. 1994;14:77-84.

Rand ML, Leung R, Packam MA. Platelet function assays. Transfus Apher Sci. 2003;28:307-317.

Aho M, Lehtinen AM, Erkola O. The effect of intravenously administered dexmedetomidine on perioperative hemodynamics and isoflurane requirements in patients undergoing abdominal hysterectomy. Anesthesiology. 1991;74:997-1002.

Jalonen J, Hynynen M, Kuitunen A. Dexmedetomidine as an anesthetic adjunct in coronary artery bypass grafting. Anesthesiology. 1997;86:331-345.

Virtanen R, Savola J-M, Saano V. Characterization of the selectivity, specifity, and potency of medetomidine as an α2-adrenoceptor agonist. Eur J Pharmacol. 1988;150:9-14.

Winther K, Klysner R, Geisler A. Characterization of human platelet beta-adrenoreceptors. Thromb Res. 1985;40:757-767.

Hjemdahl P, Larsson PT, Wallen NH. Effects of stress and beta-blockade on platelet function. Circulation. 1991;84(^s6):V144-V161.

Grant JA, Scrutton MC. Interaction of selective α-adrenoceptor agonists and antagonists with human and rabbit blood platelets. Br J Pharmacol. 1980;71:121-134.

Kambayashi J-I, Shinoki N, Nakamura T. Prevalence of impaired responsiveness to epinephrine in platelets among Japanese. Thromb Res. 1996;81:85-90.

Von Kanel R, Dimsdale JE. Effects of sympathetic activation by adrenergic infusions on hemostasis in vivo. Eur J Hematol. 2000;65:357-369.

Petidis K, Douma S, Doumas M. The interaction of vasoactive substances during exercise modulates platelet aggregation in hypertension and coronary artery disease. BMC Cardiovasc Disord. 2008;27(8).

Martins CR, Tardelli MA, Amaral JL. Effects of dexmedetomidine on blood coagulation evaluated by thromboelastography. Rev Bras Anestesiol. 2003;53:705-719.

Stump DC, Macfarlane DE. Clonidine and para-aminoclonidine, partial agonists for the alpha2-adrenergic receptor on intact human blood platelets. J Lab Clin. 1983;102:779-787.

Petrusewicz J, Kaliszan R. Human blood platelet alpha adrenoceptor in view of the effects of various imidazol(in)e drugs on aggregation. Gen Pharmacol. 1991;22:819-823.

Hsu CY, Knapp DR, Halushka PV. The effects of alpha adrenergic agents on human platelet aggregation. J Pharmacol Exp Ther. 1979;208:366-370.

Hikasa Y, Abe M, Satoh T. Effects of imidazoline and non-imidazoline alpha-adrenergic agents on canine platelet aggregation. Pharmacology. 1999;58:171-182.

Piletz JE, Sletten K. Nonadrenergic imidazoline-binding sites on human platelets. J Pharmacol Exp Ther. 1993;267:1493-502.

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