Herman G, Mauduit P, Rossignol B
Scand J Clin Lab Invest Suppl. 1981;156:309-12. doi: 10.3109/00365518109097499.
In the present paper we report the effect of two methylxanthines (pentoxifylline and isobutylmethylxanthine) on the protein secretion in a model of exocrine gland (rat lacrimal gland). Both compounds are able to increase the protein release. This effect is dependent on the calcium concentration gradient between the extra- and intracellular media. The larger the difference, the greater the pentoxifylline or isobutylmethylxanthine effect. Moreover, pentoxifylline and isobutylmethylxanthine can potentiate the norepinephrine or isoproterenol effect by inhibiting phosphodiesterases (even in the absence of calcium). All these data suggest pentoxifylline and isobutylmethylxanthine can act on the cell functions in two ways: (a) by a calcium-dependent mechanism, either by increasing the influx of calcium into the cell or by mobilizing the pool of intracellular calcium; (b) by a mechanism independent of calcium and dependent on a system involving cyclic nucleotides. The first possibility seems to be very attractive for further investigations of the mechanism of action of pentoxifylline and especially when this drug is used to affect the cell motility or deformability controlled by calcium.
在本论文中，我们报告了两种甲基黄嘌呤（己酮可可碱和异丁基甲基黄嘌呤）对外分泌腺（大鼠泪腺）模型中蛋白质分泌的影响。两种化合物均能增加蛋白质释放。这种作用取决于细胞外和细胞内介质之间的钙浓度梯度。差异越大，己酮可可碱或异丁基甲基黄嘌呤的作用就越强。此外，己酮可可碱和异丁基甲基黄嘌呤可通过抑制磷酸二酯酶来增强去甲肾上腺素或异丙肾上腺素的作用（即使在没有钙的情况下）。所有这些数据表明，己酮可可碱和异丁基甲基黄嘌呤可通过两种方式作用于细胞功能：（a）通过钙依赖性机制，要么增加钙流入细胞，要么动员细胞内钙库；（b）通过独立于钙且依赖于涉及环核苷酸的系统的机制。第一种可能性对于进一步研究己酮可可碱的作用机制似乎非常有吸引力，尤其是当该药物用于影响由钙控制的细胞运动性或可变形性时。
