The Relative Reaction Within Living Mammalian Tissues

Abstract

By means of vital staining with indicators a study has been made of the changes in reaction and in certain other attributes of a tissue abruptly rendered ischemic. Grafts of mouse skin have been employed as test material. It has been found that almost at once after implantation vigorous grafts become notably acid as compared with the normal skin and that they survive and "take" despite the acid condition, which remains at a maximum for several days. Weak or injured grafts on the contrary tend to be as alkaline as their surroundings, if not more so. Through experiments directed to the purpose reasons for this difference have been found in the lessened metabolic activities of the cells of the injured skin, and in an increased permeability which leads to a generalized suffusion of the damaged tissue with the alkaline lymph and an abnormally rapid escape of carbon dioxide from it. The influence of these factors to determine the reaction of tissues dying within the body has not been sufficiently taken into account in considering the chemical changes that occur after cell death, and some revision of current views regarding these as they affect small necrotic masses would seem called for. Carbon dioxide penetrates so readily into the living skin as to cause some local increase in the hydrogen ion concentration within cutaneous regions exposed to an atmosphere of it, even when the local circulation and the ventilation by way of the lungs have not been interfered with. It penetrates injured skin with especially great ease. Tissue acidosis and edema not infrequently occur together; but no relationship between them of cause and effect has been made out.

The results of vital staining with phenol red during the progress of carcinogenesis in mice treated with tar, dibenzanthracene and benzpyrene

“…Four per cent. phenol red solutions were prepared as described by Rous (1926). The specimens of phenol red (B.D.H.)…”

“…suggested that the mechanism of turnour production by the carcinogenic hydrocarbons might bear some relationship to defects in the cutaneous circulatory conditions obtaining in treated mice. The present communication reports an attempt to investigate the circulatory conditions of such mice by one of the intra-vitam indicator methods of Peyton Rous. Rous (1926) and Rous and Drury (1929) showed that if a solution of phenol red is injected intraperitoneally into a mouse or rat, the animal shows a general uniform red colouration with the dye, which develops its maximum intensity in the course of some ten minutes.…”

The Relative Reaction Within Living Mammalian Tissues

“…Litmus or erythrolitmin, already segregated within the protoplasm in the red form, turns sharply blue and dissolves out in a blue cloud (3). Dying skin grafts on animals injected with phenol red do not stain red like normal skin, or ruddy orange like healthy grafts, but a somewhat purply red, showing that they have become relatively alkaline (6). These changes are to be explained by a loss of the selective semipermeability of the cells with the consequence that the alkaline body fluids seep into them, while, in the case of skin grafts, carbon dioxide escapes through the surface epithelium.…”

Studies of Tissue Maintenance

“…The organs of special interest were first looked at, the order of inspection being purposely varied to rule out the possibility of errors due to post-mortem diffusion of the dye. The intensity of the staining as viewed in the gross, was frequently recorded in terms of Ridgway's color standards (9) according to the method used in previous investigations (10). Save in special instances we have not concerned ourselves with the precise location of the dye within the tissues, the main point being that it should have left the circulation, have been served up to the ceils, so to speak, irrespective of acceptance or rejection by them.…”