” All experiments were performed on a total of 192 New Zealand albino rabbits.
Papain (purified powder papain, Sterling-Winthrop, Inc, New York) was injected intravenously, with a constant infusion pump, into the marginal vein of the ear as a 1.5% aqueous solution; 35 mg/kg were injected over a 15-minute period.
Animals received diethylstilbestrol diphosphate (Dome Laboratories, a division of Miles Laboratories, Inc, New York, New York) 2 mg/kg body weight daily, intramuscularly, for 15 consecutive days.
The permeability of articular cartilage was tested by the method of Stockwell and Barnett. “
The effect of aging and that of papain and certain steroid hormones upon the permeabilitv of articular cartilage was studied in 192 New Zealand albino rabbits. Two age groups were studied, adolescents and adults. The permeability of articular cartilage decreased with aging; the permeability index of the adult group was significantly lower when compared with that of adolescent group (P, t) < 0.05).
Studies in permeability of articular cartilage in New Zealand albino rabbits. The effect of aging, papain, and certain steroid hormones, The American journal of pathology, NCBI PubMed PMID: 5538720, 1971 Jan.
Papain, which has been shown to bring about changes in the chemical composition of cartilage matrix similar to those due to the aging process, decreased the permeability of articular cartilage in adolescent animals. Adult animals were not affected by papain.
Three different steroid hormones were tested: cortisone, estrogen and testosterone. Of all the steroids used, cortisone seems to be the most effective in increasing the permeability of articular cartilage, particularly in adult rabbits. Of the groups of animals treated with steroidpapain, the estrogen-treated adolescent group was relatively resistant to papain; of the adult groups, only the cortisone-treated group responded to papain. This may suggest a difference in the mode of action of the steroids studied.
Click to download the full study PDF.