Spooner P R
International Laboratory for Research on Animal Diseases, Nairobi, Kenya.
Parasitology. 1990 Dec;101 Pt 3:387-93. doi: 10.1017/s0031182000060583.
Oxytetracycline (OTC) significantly inhibited cytochrome c oxidase activity in bovine lymphocytes infected with Theileria parva and in uninfected mitogen-stimulated lymphocytes. The inhibitory effect was detected in vitro within 24 h of treatment with drug concentrations as low as 1 micrograms/ml. Following mitogen stimulation of lymphocytes, concentrations of 3 and 10 micrograms/ml OTC completely inhibited an increase in cytochrome c oxidase activity for 48-72 h. This inhibitory activity was considered to be due to a direct effect on lymphoblast mitochondrial protein synthesis. As a consequence, adenosine triphosphate activity was significantly reduced in lymphocytes stimulated either by infection with T. parva sporozoites or by mitogen and then treated with OTC. The results also indicated that parasite mitochondrial protein synthesis was inhibited by OTC. The activity of OTC reported in this study could explain the suppression of disease following 'infection and treatment' immunization against East Coast fever and the in vitro drug-inhibition of schizont development.
土霉素（OTC）能显著抑制感染小泰勒虫的牛淋巴细胞以及未感染的经丝裂原刺激的淋巴细胞中的细胞色素c氧化酶活性。在体外，用低至1微克/毫升的药物浓度处理24小时内即可检测到这种抑制作用。淋巴细胞经丝裂原刺激后，3微克/毫升和10微克/毫升的土霉素浓度可在48 - 72小时内完全抑制细胞色素c氧化酶活性的增加。这种抑制活性被认为是由于对淋巴母细胞线粒体蛋白质合成的直接作用。因此，无论是用小泰勒虫子孢子感染刺激还是用丝裂原刺激然后用土霉素处理的淋巴细胞，其三磷酸腺苷活性都显著降低。结果还表明，土霉素可抑制寄生虫线粒体蛋白质合成。本研究中报道的土霉素活性可以解释“感染并治疗”免疫接种预防东海岸热后疾病的抑制以及裂殖体发育的体外药物抑制作用。
