Abstract: Provided is a novel means of inhibiting fertilized egg fragmentation. The present invention provides an inhibitor of fertilized egg fragmentation, said inhibitor comprising selenoneine or ergothioneine, a tautomer or dimer thereof, or a pharmaceutically acceptable salt of the same as an active agent.

Abstract: An object of the invention is to provide a non-human animal which can be utilized as a model animal well exhibiting a pathological condition of low-turnover type of osteoporosis and chronic obstructive pulmonary disease, for screening therapeutic agents for osteoporosis or therapeutic agents for chronic obstructive pulmonary disease, etc. The invention includes a non-human animal, wherein a gene coding for CD9 and a gene coding for CD81 are deficient at least in somatic cells; and a method to use the non-human animal as an osteoporosis model animal, including a step of measuring the degree of inhibition in the osteogenesis, and a method to use the non-human animal as a chronic obstructive pulmonary disease model animal, including a step of measuring the degree of a phenotype similar to chronic obstructive pulmonary disease.

Abstract: The present invention provides a method, upon introducing an extracellular substance, such as sperm, a cell nucleus, a nucleic acid, and a protein, into a mammalian oocyte, for introducing the extracellular substance into a mammalian oocyte, which is safe for the mammalian oocyte, enables efficient introduction, and is technically easy. By treating the mammalian oocyte with a tubulin-polymerization inhibitor such as vinblastine, membrane fusion between the oocyte and the sperm is promoted, and the sperm and the oocyte are fused without making a hole in the oolemma and fertilization can be achieved. The method of the present invention can be applied not only to the case of introducing sperm into a mammalian oocyte, but also to the case of introducing an extracellular substance, such as a cell nucleus, a nucleic acid, and a protein, into a mammalian oocyte.

Abstract: An object of the invention is to provide a non-human animal which can be utilized as a model animal well exhibiting a pathological condition of low-turnover type of osteoporosis and chronic obstructive pulmonary disease, for screening therapeutic agents for osteoporosis or therapeutic agents for chronic obstructive pulmonary disease, etc. The invention includes a non-human animal, wherein a gene coding for CD9 and a gene coding for CD81 are deficient at least in somatic cells; and a method to use the non-human animal as an osteoporosis model animal, including a step of measuring the degree of inhibition in the osteogenesis, and a method to use the non-human animal as a chronic obstructive pulmonary disease model animal, including a step of measuring the degree of a phenotype similar to chronic obstructive pulmonary disease.