Urocanic acid isomers in human skin: analysis of site variation.

Urocanic acid analogues and the suppression of the delayed type hypersensitivity response to Herpes simplex virus.

Ultraviolet irradiated urocanic acid (4-imidazoleacrylic acid) containing a mixture of cis- and trans-isomers has been shown previously to induce suppression of the delayed type hypersensitivity (DTH) response to Herpes simplex virus type 1 (HSV-1) in a murine model of infection. The cis-isomer of urocanic acid was prepared and the cis- and trans-isomers of 2-methylurocanic acid. 2-pyrroleacryl...

Electronic spectra, structure and photoisomerization of urocanic acid

-Electronic absorption and fluorescence spectra of urocanic acid are studied in aqueous solution at different pH. The observed results are explained using molecular orbital geometry optimization calculations for the ground states of a number of tautomers of urocanic acid including those of its anion, followed by calculation of electronic transitions. The isomers of urocanic acid which would str...

Some photophysical studies of cis- and trans-urocanic acid.

Urocanic acid, an important human skin chromophore, undergoes a variety of photochemical transformations when exposed to the near-UV portion of sunlight and natural daylight, the principal reaction being the transformation from the stable trans- or (E)-form of the chromophore (trans-UA) to the biologically active cis- or (Z)-form (cis-UA), which is claimed to induce immunosuppression linked to ...

Quantification of urocanic acid isomers in murine skin during development and after irradiation with UVB light.

Urocanic acid has been postulated as the photoreceptor mediator of immunosuppression induced by ultraviolet-B (UVB) irradiation. We have shown previously that transplanted epidermal cells from neonatal mice, irradiated mice or mice skin painted with cis-urocanic acid suppress the immune responses to herpes simplex virus. Dorsal skin from foetal mice at 3 weeks gestation and from neonatal mice w...

Simultaneous determination of urocanic acid isomers and histidine in human stratum corneum by high-performance liquid chromatography.