As shown Nutlin-3a in vitro in Fig. 2A–C, the control levels of TEWL and TWF were both affected with the water flux into the skin increasing and water efflux out of the skin increasing in direct proportion to the degree of tape stripping. Similarly, the ER of the pig skin showed a progressive fall in response

to the number of strips taken as the resistivity of the skin sample decreased. For example, the initial batch of 5 tape strips resulted in a highly significant (p < 0.0001) 1.7-fold decrease in ER, when compared with the “control” and a highly significant (p < 0.0001) 3.5-fold increase in TEWL. Following ten tape strips, TWF increased 3.5-fold (p < 0.001), ER decreased 2.4-fold (p < 0.0001) and TEWL increased 5-fold (p < 0.0001) when compared to the unstripped control group. The trend continued with 15 tape strips

resulting in 5.8-fold increases (p < 0.0001) in TWF, 3.3-fold decreases in ER (p < 0.0001) and 5.8-fold increases in TEWL (p < 0.0001) above control. The final ER and TEWL measurements following 20 tape strips, which probably results in the complete removal of the stratum corneum, gave 4.5-fold decreases (p < 0.0001) and 8.1-fold increases LDK378 solubility dmso (p < 0.0001) compared with control, respectively. With the exception of TWF measurements following ten tape strips (p < 0.001), each batch of five tape strips resulted in a highly significant (p < 0.0001) change in the three integrity measurements when compared with the control (0 strips) value. Further investigation into the effect of individual tape stripping after the first 5 strips reinforced the sensitivity of ER in detecting initial membrane damage following the 5 tape strips and then each subsequent individual Miconazole tape strip thereafter. As shown in Fig. 3A, the ER value following 5 strips decreased

1.5-fold when compared to the “control” after which there was a small, but observable, further fall in ER of the skin membrane with each subsequent tape strip up to 14 strips. At this point there was an overall 3.4-fold decrease in ER (p < 0.0001) when compared to the “control”. The individual strip data correlated well with the grouped 5 tape strip data for ER shown in Fig. 2A–C. TEWL measurements following 5 tape strips, as shown in Fig. 3B, demonstrated a 4.8-fold increase in water efflux from the compromised skin when compared to the ‘control’ which was broadly comparable to the batches of 5 strips. However, TEWL measurements following each subsequent individual tape strip did not show a uniform pattern of increased damage as assessed by water efflux.