Figure 2.

Parathyroid hormone (PTH) promoted both blood and lymphatic vessel formation. Alendronate (ALN) had no effect on blood vessels but suppressed lymphatic vessel formation. (A) Representative photomicrographs of extraction wound sections at 21 d. The soft tissue areas in the wounds are shown. Blood and lymphatic vessels were immunofluorescently labeled with CD31 (pink) and LYVE-1 (green), respectively. DAPI (blue) counterstaining was used to visualize nuclei. Negative control (far left): Isotype controls were used instead of primary antibodies. Scale bar: 100 µm. (B) Representative photomicrographs of extraction wound sections at 10 d. The soft tissue areas above the extraction sockets are shown (top). b, bone. Scale bar: 200 µm. Images below are magnified views of the dotted white rectangles. Large blood and lymphatic vessels are noted in the PTH group versus the others. Negative control (far left): Isotype controls were used instead of primary antibodies. Scale bar: 100 µm. (C) ALN had no negative effect on the blood vessel area, while PTH significantly promoted blood vessels at 5 and 10 d. (D) A significantly larger lymphatic vessel area was noted at 5, 7, and 10 d in the PTH group, while a significantly smaller lymphatic vessel area was noted at 5 and 21 d in the ALN group. n = 7/group. *P < 0.05, **P < 0.01, and ***P < 0.001 versus vehicle control (VC). ^##P < 0.01 versus PTH.