Murine model of hind limb ischemia: mecamylamine inhibits ischemia-induced angiogenesis. Saline or increasing concentrations of mecamylamine were administered by daily intramuscular injections into the ischemic hind limb. (a) As compared with control, mecamylamine decreased capillary density. Results are shown as box plots displaying 25th and 75th percentiles as boxes and 5th and 95th percentiles as thin lines. n = 5; *P < 0.01 vs. control. i.m., intramuscular; s.c., subcutaneous. (b and c) At base line (no ischemia), the α7 subunit (red fluorescence) was not detectable by immunohistochemistry (capillaries identified by CD31, green fluorescence). (d and e) However, 7 days after induction of ischemia in the hind limb and no treatment, the α7 subunit of the nAChR was clearly detectable (red fluorescence) and mainly colocalized with CD31 (yellow fluorescence). Representative pictures are shown. (f) These results were confirmed by Western blot analyses demonstrating upregulation of the α7-nAChR subunit within 24 hours after onset of ischemia and a maximal effect at 7 days.