The effect of the removal of the endolymphatic duct and sac anlage upon organogenesis of the mammalian inner ear "in vitro": A preliminary report

Preliminary observations of the effect of surgical excision of the endolymphatic duct and sac anlage in normal mouse embryo inner ear embryogenesis "in vitro" are reported. Otocysts of twelfth and thirteenth gestation day mouse embryos were grown in organ culture for 9 and 8 days respectively. The organ culture specimens of each gestational age group were further divided into otocysts with intact endolymphatic duct and sac anlages and otocysts that had their endolymphatic duct and sac anlages surgically excised prior to explantation. The resultant histological quantification of inner ear embryogenesis did not reveal any significant differences in morphogenesis, histodifferentiation of inner ear sensory structures or presence of endolymphatic hydrops in any of the organ culture specimens. It was concluded that in the system studied the absence of the endolymphatic duct and sac anlage did not have an effect on the organogenesis of the inner ear with the exception of the resultant lack of development of an endolymphatic duct and sac.