Fig. 2. Inhibition of heparanase function decreases branching morphogenesis of mouse SMGs. Laminaran sulfate (LMS), which inhibits heparanase activity, decreases branching morphogenesis (A), whereas the unsulfated laminarin control (LM) does not. In addition, a function-blocking anti-heparanase antiserum (B) decreases branching morphogenesis in a dose-dependent manner, whereas the control serum does not. E12 SMGs were cultured in the presence of unsulfated laminarin (LM; 10 or 50 µg/ml) or LMS (10 and 50 µg/ml), a heparanase function-blocking antiserum (Ab733; 1, 2, 4 µl/well), or normal rabbit serum (4 µl/well shown) for 48 hours. The number of buds was expressed as a ratio of the number of buds at 48 hours/number of buds at 1 hour (T48/T1). At least five SMGs/condition were used and the experiment repeated at least three times. ANOVA; ^*P<0.05; ^**P<0.01.