IMMUNOHISTOCHEMICAL FINDINGS OF IGG RECOGNIZED IN THE PLANUM-SEMILUNATUM OF THE GUINEA-PIG

The planum semilunatum is located on the lateral side of the crista am pullaris of the semicircular canal. With regard to the functions of th e planum semilunatum, some researchers assume the existence of secreto ry activity based on the microstructural features observed in isotopic experiments. In the present study, in order to confirm the existence of an immunological mechanism in the ampulla of the semicircular canal , the distribution of immunoglobulins in the semi-circular canal of gu inea pigs was investigated immunohistochemically. Positivity of IgG wa s observed in the constituent cells of the planum semilunatum or benea th the basement membrane of the cells. It is concluded that ample IgG, which is an important constituent of the body fluids, is collected wi thin this region. The planum semilunatum containing such ample amounts of IgG might be involved in the immunological mechanism operating in the ampullar of the semicircular canal.