The effect of different concentrations of cryoprotector (sucrose) on the efficiency of fenoterol inclusion in the lipid matrix during lyophilization has been studied. It has been shown that the liposomal form with the content of cryoprotector in the internal environment of liposomes 2.5 % and in the external environment equal to 2 % provides long-term preservation of the drug in the liposome cavity. Under these conditions, it is possible to achieve a monodisperse distribution of particles with an average diameter of 4.281.62 m. The assumed quantitative composition of the cryoprotector ensures the manufacturability of the liposome production process, increases the stability of the lyophilizate structure and prevents the particles from sticking together, ensuring their uniformity. The profile of two-stage release of fenoterol from the liposomal form has been shown in vitro. The first stage of rapid release was characterized by a transition to free form within 15 minutes to 42 % of the encapsulated fenoterol. At the second stage, the active principle was released more slowly for 480 minutes. The model of bronchospasm induced by 1% histamine has shown the advantage of the liposomal form of fenoterol in comparison with its free form in the form of an aqueous solution. Intra-tracheal administration of the liposomal form of fenoterol at a dose of 17 ukg/kg provided for 360 minutes the preservation of external respiratory function at the level of initial values, despite histamine inhalation, while the duration of action of fenoterol did not exceed 120 minutes.
РезюмеВ экспериментальной модели дыхательной недостаточно-сти, вызванной однократным внутрибрюшинным введени-ем параквата в дозе 1 LD 50 (24 мг/кг), исследовано изме-нение толерантности к физической нагрузке, параметров функции внешнего дыхания, а также гистоархитектоники такни легких. На модели дыхательной недостаточности у крыс проведено исследование анальгетической активно-сти, токсичности и безопасности фентанила, дексмедетоми-дина и комбинации на их основе в сравнении с интактными животными. Показано, что на фоне патологии легких для каждого из рассматриваемых средств наблюдается сниже-ние среднелетальных доз в среднем на 13-28 %. В отли-чие от монопрепаратов, применение комбинации средств не сопровождается снижением среднеэффективной обез-боливающей дозы и характеризуется сохранением широты терапевтического действия у крыс с дыхательной недоста-точностью. Keyword:fentanyl; dexmedetomidine; respiratory failure; combination therapy. AAdsoras.In an experimental model of respiratory failure induced by a single intraperitoneal injection of 1 LD 50 of paraquat (24 mg/kg) the changes of physical activity tolerance, respiratory function parameters were studied and histomorphologic validation of experimental results was confirmed. In a model of respiratory failure the assessment of analgesic activity and toxicity of fentanyl, dexmedetomidine and their combination was made and compared with intact animals. The integral tolerance rates (therapeutic action width) were also estimated. It was shown that on the background of pulmonary pathology for each of the drugs 13-28% decrease of average lethal doses was observed. At the same time when administered in combination an average effective dose of the drugs wasn't changed in contrast with single-drug analgesia. ВВедеНИеПо данным Всемирной организации здравоохра-нения, неуклонно растет величина показателя смерт-ности пациентов с хронической дыхательной недо-статочностью (ХДН), обусловленной хронической обструктивной болезнью легких (ХОБЛ). По прогнозам сообщества, к 2030 году ХОБЛ, осложненная дыха-тельной недостаточностью, выйдет на третью позицию по причине летальности в мире [1]. Согласно данным эпидемиологического наблюдения на сегодняшний день насчитывается более 11 млн пациентов с ХДН [2,3].
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