1. cis-Urocanic Acid Stimulates Neuropeptide Release from Peripheral Sensory Nerves 
Zeinab Khalil 
Journal of Investigative Dermatology 
Volume 117, Issue 4, Pages (October 2001)
DOI: /j x x
Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions

2. Figure 1
The effect of cis-UCA on microvascular blood flow. (A) Dose-dependent increase in microvascular blood flow in response to cis-UCA perfused for 20 min over the base of a blister raised on the hind footpad of naïve rats. cis-UCA was perfused at concentrations of 100 µM, 1 mM, and 10 mM for six to eight rats per group. An asterisk denotes significantly different from cis-UCA at 1 mM. (B) The effect of trans-UCA and cis-UCA (each at 10 mM) perfused for 20 min in isolation or together on microvascular blood flow recorded from the base of blisters raised on the hind footpad of naïve rats. For six to eight rats per group, trans-UCA did not induce a change in baseline blood flow. cis-UCA alone induced an increase in microvascular blood flow that was not significantly different from the response obtained to combined perfusion of both cis-UCA and trans-UCA.
Journal of Investigative Dermatology  , DOI: ( /j x x)
Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions

3. Figure 2
The effect of receptor antagonists to substance P and CGRP (RP and CGRP8-37, respectively, each at 10 µM) on the vascular response to cis-UCA (10 mM). For six to eight rats per group, vascular responses were recorded from the base of blisters raised on the hind footpads of naïve rats. The antagonists (alone or in combination) were perfused for 10 min prior to and concomitant with cis-UCA. An asterisk denotes a significant difference from cis-UCA (10 mM). A cross denotes a significant difference from cis-UCA (10 mM) in the presence of RP alone.
Journal of Investigative Dermatology  , DOI: ( /j x x)
Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions

4. Figure 3
The effect of substance P and CGRP receptor antagonists (RP and CGRP8-37, respectively, each at 10 µM) on the vascular response to cis-UCA (10 mM) in sensory-neuropeptide-depleted rats. For six to eight rats per group, vascular responses were recorded from the base of blisters raised on the hind footpads of capsaicin-pretreated rats. The receptor antagonists (alone or in combination) were perfused for 10 min prior to and concomitant with cis-UCA. No significant differences were observed between groups.
Journal of Investigative Dermatology  , DOI: ( /j x x)
Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions

5. Figure 4
The effect of UVB and cis-UCA on the CHS responses of sensory-neuropeptide-depleted and control BALB/c mice to the hapten, TNCB. Four-week-old mice were injected subcutaneously in the neck region with capsaicin (25 mg per kg) on two consecutive days. After a further 4 wk, in (A) mice were untreated or irradiated with 8 kJ per m2 UVB. In (B) mice were injected subcutaneously on their backs with cis-UCA (200 µg per mouse) or, as a control, trans-UCA (200 µg per mouse). The mean change in ear swelling (+ SEM) for five mice per group is shown; the groups of mice were always coded before challenge with hapten and ear thickness measurements. An asterisk denotes a result significantly different (p <0.05) from that of nonirradiated mice in (A) or mice treated with trans-UCA in (B).
Journal of Investigative Dermatology  , DOI: ( /j x x)
Copyright © 2001 The Society for Investigative Dermatology, Inc Terms and Conditions