Menardi Antonio Carlos, Capellini Verena Kise, Celotto Andrea Carla, Albuquerque Agnes Afrodite Sumarelli, Viaro Fernanda, Vicente Walter Vilella A, Rodrigues Alfredo José, Evora Paulo Roberto Barbosa
Department of Surgery and Anatomy, FMRP, USP, Ribeirao Preto, SP, Brazil.
Acta Cir Bras. 2011 Dec;26(6):481-9. doi: 10.1590/s0102-86502011000600013.
To verify if the methylene blue (MB) administration prevents and/or reverses the compound 48/80 (C48/80)-induced anaphylactic shock in pigs.
Female Dalland pigs were anesthetized and had the hemodynamic parameters recorded during the necessary time to administer some drugs and observe their effect. The animals were randomly assigned to one of the five groups: 1) control; 2) MB: the animals received a bolus injection of MB (2 mg/kg) followed by continuous infusion of MB (2.66 mg/Kg/h delivered by syringe infusion pump); 3) C48/80: the animals received a bolus injection of C48/80 (4 mg/kg); 4) C48/80+MB: the animals received a bolus injection of C48/80 (4 mg/kg) and 10 minutes after the C48/80 administration the animals received a bolus injection of MB (2 mg/kg) followed by continuous infusion of MB (2.66 mg/Kg/h delivered by syringe infusion pump); 5) MB+C48/80: the animals received a bolus injection of MB (2 mg/kg) and 3 minutes later they received a bolus injection of C48/80 (4 mg/kg).
The intravenous infusion of MB alone caused no changes in the mean arterial pressure (MAP) showing that the administered MB dose was safe in this experimental model. The C48/80 was effective in producing experimental anaphylactic shock since it was observed a decrease in both MAP and cardiac output (CO) after its administration. The MB did not prevent or reverse the C48/80-induced anaphylactic shock in this model. In fact, the MAP of the animals with anaphylactic shock treated with MB decreased even more than the MAP of the animals from the C48/80 group. On the other hand, the C48/80-induced epidermal alterations disappeared after the MB infusion.
Despite our data, the clinical manifestations improvement brings some optimism and does not allow excluding the MB as a possible therapeutic option in the anaphylactic shock.
验证亚甲蓝（MB）的给药是否能预防和/或逆转化合物48/80（C48/80）诱导的猪过敏性休克。
对雌性达兰猪进行麻醉，并在给予某些药物并观察其效果的必要时间内记录血流动力学参数。动物被随机分为五组之一：1）对照组；2）MB组：动物先接受一次MB推注（2mg/kg），随后通过注射器输液泵持续输注MB（2.66mg/Kg/h）；3）C48/80组：动物接受一次C48/80推注（4mg/kg）；4）C48/80+MB组：动物接受一次C48/80推注（4mg/kg），在给予C48/80后10分钟，动物接受一次MB推注（2mg/kg），随后通过注射器输液泵持续输注MB（2.66mg/Kg/h）；5）MB+C48/80组：动物接受一次MB推注（2mg/kg），3分钟后接受一次C48/80推注（4mg/kg）。
单独静脉输注MB未引起平均动脉压（MAP）变化，表明在此实验模型中所给予的MB剂量是安全的。C48/80能有效诱导实验性过敏性休克，因为在给药后观察到MAP和心输出量（CO）均下降。在该模型中，MB不能预防或逆转C48/80诱导的过敏性休克。事实上，接受MB治疗的过敏性休克动物的MAP下降幅度甚至比C48/80组动物的MAP下降幅度更大。另一方面，在输注MB后，C48/80诱导的表皮改变消失。
尽管我们的数据如此，但临床表现的改善带来了一些乐观情绪，并且不能排除MB作为过敏性休克可能的治疗选择。
