Nature of the Ground Substance in Interstitial Connective Tissue

Abstract

DAY1,2,3 has recently concluded that the cementing substance (the so-called amorphous ground substance) of the interstitial connective tissue is protein and not mucoid. We have now obtained some evidence in support of this conclusion by histological examination of this tissue from the deep fascia of the rat. Squares of tissue were attached at the four corners to micro-slides by means of collodion3. Some of the slides were immersed for several days in physiologically isotonic saline, some in 60 per cent ethyl alcohol and some in a saturated mercuric chloride solution. In order to try to ensure that a negative staining result would not be obtained merely because any mucoid present had been dissolved out, some of the slides, after the alcohol and saline treatments, were fixed in 10 per cent formalin for ten minutes, some by exposure to formalin vapour4, and some were stained without further fixation. The tissue was then stained by toluidine blue5, by McManus's method of periodic acid followed by Schiff's reagent6,7 or by Hale's method of dialysed iron followed by potassium ferrocyanide8. Some of the alcohol preparations were also impregnated with silver by Foot's method9.