The density and nerve varicosity-smooth muscle cell separation of rabbit cerebral and ear arterial beds were compared. The rabbit middle cerebral artery and three of its successive branches and a comparable-sized ear artery and two branches were perfusion-fixed for electron microscopy and analyzed by quantitative morphometric procedures. The purpose was to determine if there are structural corr...

The tyrosinase gene was selected as a candidate for uncovering genetic mechanism causing “black ear” coat color in rabbits. A PCR-SSCP detection method was established for the 881→881 mutation located in the central region of the tyrosinase gene between the CuA and CuB binding region signatures, and this was confirmed by sequencing and alignment. Fully consistent associations between the SNP an...

Regeneration of the amphibian limb after amputation depends on division of blastemal cells, the progenitor cells of the regenerate. This division is controlled, at least in the early stages of regeneration, by the nerve supply to the blastema. A monoclonal antibody to newt blastema cells has provided evidence that Schwann cells and muscle fibers contribute to the blastema, and identifies blaste...

Axolotls (Ambystoma mexicanum) can completely regenerate lost limbs, whereas Xenopus laevis frogs cannot. During limb regeneration, a blastema is first formed at the amputation plane. It is thought that this regeneration blastema forms a limb by mechanisms similar to those of a developing embryonic limb bud. Furthermore, Xenopus laevis frogs can form a blastema after amputation; however, the bl...

While mammals have a limited capacity to repair bone defects, zebrafish can completely regenerate amputated bony structures of their fins. Fin regeneration is dependent on formation of a blastema, a progenitor cell pool accumulating at the amputation plane. It is unclear which cells the blastema is derived from, whether it forms by dedifferentiation of mature cells, and whether blastema cells a...

In mammals, the loss of a limb is irreversible. By contrast, urodele amphibians and teleost fish are capable of nearly perfect regeneration of lost appendages. This ability depends on direct interaction between the wound epithelium and mesenchymal progenitor cells of the blastema. It has been known for decades that contact between the wound epithelium and the underlying blastema is essential fo...

Animals capable of regenerating multiple tissue types, organs, and appendages after injury are common yet sporadic and include some sponge, hydra, planarian, and salamander (i.e., newt and axolotl) species, but notably such regenerative capacity is rare in mammals. The adult MRL mouse strain is a rare exception to the rule that mammals do not regenerate appendage tissue. Certain commonalities, ...

Zebrafish can completely regenerate amputated fins via formation of a blastema, a proliferative mass of undifferentiated precursor cells. During regenerative growth, blastema proliferation must be tightly coordinated with cellular differentiation, but little is known about how this is achieved. Here, we show that Notch signaling is essential for maintenance of blastema cells in a proliferative ...

Zebrafish have the capacity to regenerate several organs, including the heart and fins. Fin regeneration is epimorphic, involving the formation at the amputation plane of a mass of undifferentiated, proliferating mesenchymal progenitor-like cells, called blastema. This tissue provides all the cell types that form the fin, so that after damage or amputation the fin pattern and structure are full...

the purpose of the work presented here was to investigate endotheliumdependent relaxations in the rabbit coronary ligation model of heart failure. we investigated endothelium-dependent relaxations at the level of larger vessels (thoracic aorta and vena cava left renal artery and left renal vein lateral saphenous artery and lateral saphenous vein and finally central ear artery and marginal ear v...