ACTION OF ANTIPERSPIRANTS 793 Figure •. Methylene blue iontophoretic pattern in alu- minton salt treated area. The coarse, darker puneta are produced by greater transductal permeation of the dye and more extensive epidermal staining surrounding epidermal tissue (8). To accomplish this, the sweat glands must be active and their lumina patent. To test for these conditions, an attempt was made to produce pore patterns in the formalin and aluminum sites of anhidrosis. Thus, after the obligate one hour delay to negate the effects of hydration, a 0.1% methylene blue solution was iontophorized into the treated areas using 0.5-0.75 ma/cm • for 5 min- utes. It was not possible to produce an eccrine pore pattern in the formalin treated skin. Since the stripping experiment already demonstrated superficial blockage, passage of the dye into the ducts was not expected. In the aluminum-salt treated site, however, not only was the characteris- tic blue pattern present, but the puneta were sharper and larger (Fig. 4). It was thus ascertained that the ducts were patent and the glands func- tioning. As regards the augmented pattern, it was shown that this was due to increased transductal permeation of the methylene blue and wider diffusion into the surrounding epidermis. It now remained for histologic studies to verify these gross observations.

794 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS •..•. ..... •:..C•'• •*...•:... ...: . . Figure 5. Biopsy of formalin treated skin before forced sweating. Amorphous material is seen plugging the uppermost coils of the duct within the stratum corncure. These masses are removed by the stripping procedure and allow sweat to flow onto the skin surface again. Note that the duct is not dilated. (H. & E. 25()X) •.. ,,: ...• . -*'•. .- . :. "' -:: .... •g. ---... -.,.. -:• . ::. ß • • •":• •:': ' •" • ½4 •..• ' 7 : ": • '• •:•[• • Fig•re 6. Formalin treated site after sweat stress, demonstrating distension of the sweat duct and accmnulation of intra- luminal masses of PAS positive diastase resistant material. These serial sections show the depth amt extent of the ductal dilatation resulting from sweating into the plugged eccrinc unit. Note the absence of periductal inflammation as seen in alumi- num anhidrosis. (PAS with diastase di- gesti(m X 100) Effec! •J' Forced Sweating in..4 nhidrotic Sites Biopsy samples from each treated, unstripped, anhidrotic site and control volar forearm skin were obtained from five subjects immediately after removal of the occlusive patches. The men were then sweated for one hour and repeat specimens taken from sites adjacent to the prior biopsy. Tissues were fixed overnight in 10% neutral buffered formalin and sections stained with hematoxylin and eosin (H. & E.) and periodic Acid-Schiff (PAS), with and without diastase digestion. The purpose of the sweat stress imposed on the subjects between the biopsy procedures was to assess the functional state of the secretory glands and to observe the effect of forcing perspiration into a duct which in the case of formalin treatment was presumed occluded, but more sus- ceptible to transductal permeation in the case of aluminum salt induced anhidrosis.