Pharmacological Studies on the Mechanisms of Itch-Pain and Oedema in Dermatomycosis

Abstract

The capillary permeability was measured by dye (azovan blue) accumulation in the skin of rats. The dye accumulation was investigated after i. d. injection of tyramine, histamine, serotonin, dopamine, N-acetyltyramine, N-acetylhistamine and N-acetylserotonin in the reserpinized rats, compound 48/80-treated rats and in the non-treated rats.(1) The marked increase in capillary permeability was elicited after i. d. injection of histamine and serotonin in the non-treated rats. Other biogenic amines and N-acetylated amines also increased capillary permeability weakly.(2) The marked increase in capillary permeability was elicited after i. d. injection of histamine and serotonin in the reserpinized rats. And increase in the capillary permeability after serotonin in the non-reserpinized rats was significantly reduced (p<0.01) when compared with that in the reserpinized rats, but not significant after histamine. In the cases of other biogenic amines and N-acetylated amines, there was a significant reduction (p<0.01-p<0.005) in the capillary permeability after i. d. injection of above mentioned substances in the reserpinized rats when compared with non-reserpinized rats.(3) The marked increase in capillary permeability was elicited after i. d. injection of histamine and serotonin in the compound 48/80-treated rats, which was not significant when compared with non-treated rats (compound 48/80). Moreover, the weak increase in capillary permeability was also elicited after i. d. injection of other biogenic amines and N-acetylated amines, which was significantly reduced (p<0.01-p<0.005) when compared with non-treated rats (compound 48/80), but not significant after N-acetylserotonin and dopamine.(4) Increase in the capillary permeability after biogenic amines was significantly stronger than that after N-acetylated amines (p<0.01-p<0.005) except tyramine and N-acetyltyramine.