One of the most interesting subjects in the field of dermatology has become the clarifying of the action mechanism of various drugs in promoting skin permeability in regard to their usefulness or harmfulness to various skin diseases. Although dimethyl sulfoxide (bMSO) detergents and propylene glycol were well known as having a promoting -effect on the skin permeability, but the exact action mechanism of them was still unknown because of difficulty in methodology.
So an attempt to clarify the action mechanism and find out the differences in the mode of action between them have been made by using frog skin, which. has been used in research for the `membrane transport´, during past but having complex structures i.e. soley as ´skin´ in this study was done.
Abdominal skin was removed from frogs, Rana nigromaculata, captured on the area of Kyung Ki Do. In a series of experimental procedures about effect of experimental agents, short circuit current (SCC) as an estimate of net flux of sodium transport and potential difference (PD) was measured by the method of Ussing and Zerahn(1951). And changes of SCC and PD was observed during treatment with bathing mediums which contained agents and maintained iso-osmorality by varying amount of sodium chloride. These were compared including the effect of concentration of each experimental agent. The experimental agents used were DMSO and various detergent, i.e., sodium lauryl sulphate(SLS): anionic detergent, benzalkonium chloride (BAQ : cationic detergents, and Tween-80: nonionic detergents. Results obtained are summarized on the followings.
1. The promoting effect of the sodium lauryl sulphate on the active sodium transport was reached to maitimum within 10 to 20 min. and was present until 40 min. after bathing with it, and thereafter, sodium transport was inhibited irreversibly at the both sides of the frog skin. And the maximal promoting effect of the SIS induced by increasing concentration had relationship in such a way on the saturation curve.
2. The active sodium transport was always increased on the inside of the frog skin after bathing with benzalkonium chloride (BAC) and in spite of changing of bathing medium with Ringer´s solution, the active sodium transport was steadily increased even beyond the effect of BAC except temporally decreasing just after the bathing with Ringer´s solution. But the frog skin died within 20 min. at the outside after bathing with BAC.
3. Tween-80 brought about reversible reaction increasing the active sodium transport across the frog skin af the inside after bathing. And it seemed to be parallel to the degree of the concentration of it.
4. The effect of dimethyl sulfoxide (DMSO) on the active sodium transport across the frog skin was altered seasonaly, i.e., promoting sodium transport during the summer months but inhibiting it during the winter months. So it was suggested that the action of DMSO on the sodium transport depends on the metabolic rates of the frog skin and the action differed from that of ADH hormone which promotes the sodium transports only in winter months.
Also the effect of the DMSO differed from various detergents in view of seasonal variation and reversibility of the action of it.
From the above results, this experimental method should be used more preferably using isolated frog skin in the research for: clarifying the action mechanisms of the various other drugs in skin permeability.
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