Durack D T, Corey G R, Perfect J R
Rev Infect Dis. 1982 Mar-Apr;4(2):311-4. doi: 10.1093/clinids/4.2.311.
When given in combination, both trimethoprim and sulfamethoxazole penetrated well into the cerebrospinal fluid of rabbits with experimental pneumococcal meningitis, reaching concentrations that should have been adequate for synergistic killing of Streptococcus pneumoniae. However, trimethoprim-sulfamethoxazole was less effective than ampicillin in the treatment of this experimental infection. The effect of the combination on pneumococci in vivo was bacteriostatic rather than bactericidal, possibly because the number of pneumococci in the cerebrospinal fluid of the rabbits at the start of treatment was larger than that in the inoculum used for in vitro sensitivity tests.
联合使用时，甲氧苄啶和磺胺甲恶唑在患有实验性肺炎球菌脑膜炎的兔子脑脊液中均能很好地渗透，达到的浓度本应足以协同杀灭肺炎链球菌。然而，在治疗这种实验性感染时，甲氧苄啶-磺胺甲恶唑的效果不如氨苄西林。该联合用药对体内肺炎球菌的作用是抑菌而非杀菌，这可能是因为治疗开始时兔子脑脊液中的肺炎球菌数量多于用于体外药敏试验的接种菌量。
