[Osteopetrosis in mice caused by ectomesenchymal lesions].

Pathogenesis of osteopetrosis in mice homozygotic for microphthalmia (symbol mi) mutant gene has been studied. Heparin concentration in the blood of mi/mi mice was demonstrated to be 10 times as little as the normal. Administration of different doses of heparin (1, 5, 10 per g of body weight) at different intervals (2--20, 10--20 and 20--25 days including) of their postnatal development causes partial or complete normalization in the construction of the central part of diaphysis of tubular bones. The number of heparin-secreting mast cells, derivatives of the neural crest is less than normal. Osteopetrosis in mi/mi mice is an integral part of the complex syndrom produced by the damage of neural crest cells.