title: The effect of penicillin on the mortality of splenectomized mice exposed to an aerosol of Streptococcus pneumoniae type 3.
abstract: In experiment 1, splenectomized mice exposed to 1 X 10(9) colony-forming units (cfu) of type 3 Streptococcus pneumoniae experienced no mortality when given 40,000 or 4,000 units of procaine penicillin IM starting 2 days before exposure and continuing for 4 days. On day 5, Bicillin was given once in the same dosages. In experiment 2, splenectomized mice exposed to 2.2 X 10(9) cfu were significantly protected by 400 but not 40 units of penicillin when compared to controls (P less than 0.005). In experiment 3, splenectomized mice exposed to 2.7 X 10(9) cfu were significantly protected when compared to controls if 4,000 units of procaine penicillin were given either 2 days postexposure for 2 days followed by 1 day of Bicillin in the same dosage or 4 days postexposure with the same schedule and dosage (P less than 0.005 and 0.01, respectively) but not 6 days postexposure.
mesh_terms: D000336:Aerosols; D000818:Animals; D007273:Injections, Intramuscular; D051379:Mice; D010401:Penicillin G Benzathine / Q000008:administration & dosage / Q000627:therapeutic use; D010402:Penicillin G Procaine / Q000008:administration & dosage / Q000627:therapeutic use; D010406:Penicillins / Q000627:therapeutic use*; D011008:Pneumococcal Infections / Q000401:mortality* / Q000517:prevention & control; D013156:Splenectomy
chemical_list: D000336:Aerosols; D010406:Penicillins; D010402:Penicillin G Procaine; D010401:Penicillin G Benzathine