SB 234551 improves cortical collateral perfusion following permanent MCAO in the rat

Image Analyses: The perfusion delay index (PDI) was calculated from the 4 ipsilateral areas and their corresponding contralateral counterparts using the DWI image as a reference. Of these four areas, three were chosen in the cortical region and one in the striatal region. The PDI index was defined as a ratio of the mean signal intensity in the ipsilateral area to that in the contralateral counterpart and expressed as a percentage. This calculation was done only at that instance of time when the contrast uptake was maximal in the contralateral hemisphere. Analysis of variance was used followed by appropriate post-hoc comparisons with p<0.05 considered significant. Results A representative graph showing the perfusion delay index (PDI) at one cortical region is shown in Fig 1. In all the three cortical regions evaluated, we found significant differences between vehicle and 10 ug/kg/min SB-234551 group in the perfusion delay index (PDI). The 3 ug/kg/min group did not show a significant effect at any site. Moreover, neither dose had any significant effects on the striatum. The histological data confirmed the protective effects of SB-234551 by demonstrating statistically significant reductions in lesion sizes in both treatment groups (Fig. 2). Fig. 1- Percent PDI values measured from a cortical region following treatment with 10 ug/kg/min (n=10), 3 ug/kg/min (n=10), and vehicles group (n=9). A significant difference between the 10 ug/kg/min and vehicle groups was found (*p<0.01).