Figure 4.

Testosterone-induced HVC MMP activity is blocked by the MMP2/9 inhibitor SB-3CT. A–C, For 9 d after testosterone implantation, birds were given vehicle (A), the MMP2/9 inhibitor SB-3CT at 50 mg/kg (B), or SB-3CT at 100 mg/kg (C). On the ninth day (T9), the birds were killed, and their degree of HVC gelatinase inhibition was assessed by in situ zymography. D–F, Surface plot analysis of signal intensity using ImageJ; D–F individually correspond to A–C. G–I, Distribution histogram for pixel intensity; G–I correspond to A–C. Scale bars, 100 μm.