Studies in Denervation: G.--Sebaceous Secretion

Abstract

THE need for inquiries into the physiological mechanisms underlying the secretion of sebum is indicated, not only by the lack of information concerning this function of the skin, but also by the fact that it has not as yet been determined how far perversions of secretion are the cause of various pathological conditions such as seborrheeic dermatitis. In these circumstances it seemed desirable to ascertain to what extent the sebaceous glands are under the control of the nervous system. The results of an investigation directed to this end will be reported in this paper, but it is first necessary to indicate the background of the study.As is well known the sebaceous glands are holocrine in nature and the secretion is the end product of cellular disruption. On a priori grounds it would seem unlikely that these glands would be activated by nervous influences, but Boeke (1934) has described a plexus of nerves investing the glands. He considered it to be sympathetic in origin and excitor in function though he noted that the individual cells are not innervated. Moreover, many authors such as Stein (1926), Pachur (1931), and Serrati (1938 have reported that sebaceous secretion is disturbed in various affections of the central nervous system, most notably in chronic encephalitis lethargica. Details of unilateral disturbances of secretion are furnished by Serrati.This has led to the tacit assumption that the sebaceous glands are activated directly by nerves. In further support of this position are the observations of Arloing (1891) known as to the existence or not of any action of the nervous system upon the sebaceous glands." MethodThe method used to assay the amount of sebaceous secretion is a modification of that employed by Serrati. The areas of skin under observation were wiped gently with cotton wool moistened with ether and then left exposed to the air for a time. They were then wiped thoroughly with grease free filter papers moistened with ether. The filter papers were dried in a vacuum chamber and weighed. The weight of the paper was subsequently obtained after extracting the grease with ether and drying. The difference of these weights indicated the amount of ether-soluble material which had been adsorbed on to the papers from the skin. The areas of skin on which the individual estimations were made varied from 200 to 300 sq. cm. and the results are expressed in the amount per 100 sq. cm. The limitations of the method were indicated by the following procedures. Measurements made immediately after the preliminary cleansing resulted in figures of I 0 to 2-0 mg., while a comparison of the amount of sebum obtained from two symmetrical areas on the face of a normal subject after an interval of 1 hour showed a disparity of 2 mg. on one occasion and 3 mg. on another. It would appear, therefore, that differences of 3 mg. or less as estimated by this method are without significance and may be due to incomplete removal of the sebum from the skin or to other errors introduced in weighing or in extracting the fat from the f...

Pathogenesis and treatment of acne in childhood.

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Unilateral Seborrheic Dermatitis Following a Nerve Lesion

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