Staining of the Adrenals with Neutral Silver Nitrate as a Test for Scurvy

Moore and Ray 1 and Miller, Siehrs, and Brazda 2 observed that, whereas immersion of the cut surface of the adrenal gland from a normal guinea pig in neutral silver nitrate solution resulted in a blackening of the surface of the gland, there was no reduction by adrenal glands taken from scorbutic guinea pigs. Siehrs and Miller 3 showed that staining ability of the adrenals disappeared after the animal had been on a scorbutic diet for 6 days, but reappeared even after 18 days on a scorbutic diet if the animal were then fed 3 cc. of orange juice per day until the twenty-second day. They suggest that “the reduction test is a convenient qualitative method for testing for scurvy and for antiscorbutic substances,”

The adrenals of 14 guinea pigs dying of scurvy were tested by immersion in neutral 0.4% silver nitrate solution for 30 minutes. None showed any staining. One animal fed on a scorbutic diet for 37 days was then given 1.5 cc. lemon juice daily for 4 days and was killed with ether. Its adrenals showed no staining, even after 30 minutes in silver nitrate. Four guinea pigs that had been fed on the basal scorbutic diet plus 1.5 cc. of lemon juice daily were killed respectively on the 50th, 56th, 56th, and 57th days of the diet, and a piece of sliced adrenal from each was immersed in the silver nitrate solution for 30 minutes. At the end of this time there was in every case either no change in the color of the gland, or at most only a faint graying. In one case one whole gland and half of the other were ground with sand for a moment, water was mixed in, and the solid particles were centrifuged out.