Fig. 7. Effect of PD98059, wortmannin and rapamycin on tubule formation. Matrigel cultures were maintained either with 5x10^–5 M PD98059, 5x10^–8 M wortmannin or 2.5x10^–8 M rapamycin in addition to insulin, transferrin, hydrocortisone and EGF for 2 weeks. Before confocal microscopy, the cultures were maintained for 20 hours under the same conditions, with the addition of 80 µM Lucifer Yellow and 4 µg/ml Texas Red-labeled T. vulgare, and then examined under the confocal microscope. (A) PD98059; (B) wortmannin; (C) rapamycin. Bar in A, 50 µm (for B and C).