Morandini G C, Perduca M, Finiguerra M, De Martini S, Fraticelli G
Int J Clin Pharmacol Res. 1986;6(5):415-23.
In order to explain the mechanism of action of drugs modifying the bronchial secretions, their subdivision into agents with a direct or an indirect action seems justified: the former primarily modify already formed secretions, whilst the latter act on the bronchial structures originating mucus. In hypersecretive states with increased viscoelasticity of mucus, a widespread therapy is represented by the use of direct reducing drugs, which act by breaking the mucofibrillar network. Among them the most important are those with free sulphydryl groups (-SH), which can break the disulphide bonds of the bronchial secretions. The mechanism of action of substances such as acetylcysteine and tiopronin, that are included in those with a direct reducing action, was already verified by researches with the modified thrombo-elastograph (MTE) and has been recently confirmed by the present authors by employing a simple biochemical method, by which the action of such drugs on the structure of serum IgM can be studied in vitro. The same method permits the classification of carbocisteine and letosteine as amongst the drugs with indirect action. From the results obtained by such in vitro experiences, the necessity to examine more closely the consequences of secondary effects which direct mucolytic agents may cause by modifying the rheological, biochemical and immunological properties of bronchial secretions has been demonstrated.
为了解释改变支气管分泌物的药物的作用机制，将它们细分为具有直接作用或间接作用的药物似乎是合理的：前者主要改变已形成的分泌物，而后者作用于产生黏液的支气管结构。在黏液黏弹性增加的分泌过多状态下，广泛使用的治疗方法是使用直接还原药物，这些药物通过破坏黏液纤维网络起作用。其中最重要的是那些具有游离巯基（-SH）的药物，它们可以破坏支气管分泌物的二硫键。诸如乙酰半胱氨酸和硫普罗宁等具有直接还原作用的物质的作用机制，已通过改良血栓弹性描记仪（MTE）的研究得到验证，并且最近作者通过采用一种简单的生化方法再次证实，通过该方法可以在体外研究此类药物对血清IgM结构的作用。同样的方法可以将羧甲司坦和半胱氨酸列为具有间接作用的药物。从这些体外实验获得的结果来看，已经证明有必要更仔细地研究直接黏液溶解剂通过改变支气管分泌物的流变学、生化和免疫学特性可能引起的副作用的后果。
