Application of the supravital staining method to the study of the sorptive properties of certain organs in experimental tuberculosis

Sorption of neutral red by the isolated kidneys and adrenals of guinea pigs has been determined, following inoculation of the animals with virulent or BCG cultures of bovine typeM.tuberculosis, as well as after inoculation of immunized animals with virulent culture. In contrast to other organs, the sorptive capacity of these organs falls considerably after inoculation, although similar fluctuations are seen subsequently in the sorption — time curves as with other organs (brain, muscle, spleen, Ings) during their phase of heightened affinity for the stain. Maximum sorption of neutral red coincides in time with appearance of tubercles in the kidneys, spleen, and lungs. In the kidneys, inoculation of immunized guinea pigs with virulent culture is followed, after an immediate fall in sorptive capacity, by a sustained rise to levels higher than those found in the control series or in nonimmunized animals infected with virulent culture.