FIG. 4.

Gross pathology of lungs and livers from untreated animals or animals treated with MSO and/or INH in experiment 2. Representative organs from untreated control animals or from animals treated with MSO (1.5 mg kg⁻¹ day⁻¹) alone starting on day 0, INH (4.0 mg kg⁻¹ day⁻¹) alone starting on day 14, or INH (4.0 mg kg⁻¹ day⁻¹) plus MSO (1.5 mg kg⁻¹ day⁻¹) starting on day 14 are shown. The organs were fixed in 10% formaldehyde-phosphate-buffered saline and photographed. Arrows indicate single primary tubercles, and arrowheads indicates areas where many tubercles have coalesced into a large lesion.