Peters W, Ramkaran A E
Ann Trop Med Parasitol. 1980 Jun;74(3):275-82.
More oocysts of Plasmodium yoelii developed in Anopheles stephensi if the mosquitoes received a supplement of p-aminobenzoic acid (PABA) in their diet prior to their taking an infective blood meal, than in unsupplemented control insects. The optimum concentration was 0.05% PABA in 10% sucrose. This effect was not observed if the blood meal was taken prior to feeding with PABA. Similarly, PABA administered to gametocyte-carrying mice increased the numbers of oocysts developing in mosquitoes fed on them subsequently, the effect also being dose dependent, and not mediated through an increase in gametocyte numbers. Sulphadoxine (which blocks PABA uptake) had the opposite action, reducing the numbers of oocysts either when fed directly to the mosquitoes or to the donor mice. These results are compared with those reported in other host-parasite systems by earlier workers, and certain paradoxical observations are discussed with reference to a possible relationship between sulphonamides and contaminating microorganisms in the vector mosquitoes.
如果斯氏按蚊在吸食感染性血餐之前，其饮食中添加了对氨基苯甲酸（PABA），那么约氏疟原虫的卵囊在斯氏按蚊体内发育的数量要比未添加PABA的对照昆虫体内的多。最佳浓度是在10%的蔗糖中添加0.05%的PABA。如果在喂食PABA之前就吸食了血餐，则不会观察到这种效果。同样，给携带配子体的小鼠施用PABA会增加随后以它们为食的蚊子体内发育的卵囊数量，这种效果也是剂量依赖性的，并且不是通过增加配子体数量来介导的。磺胺多辛（阻断PABA摄取）则具有相反的作用，无论是直接喂给蚊子还是喂给供体小鼠，都会减少卵囊的数量。将这些结果与早期研究人员在其他宿主 - 寄生虫系统中报告的结果进行了比较，并参考了磺胺类药物与媒介蚊子中污染微生物之间可能的关系，讨论了某些矛盾的观察结果。
