Studies On Mucous Cells Of Meretrix Meretrix Linnaeus

The types, distribution and histochemistry characters of mucous cells of Meretrix meretrix Linnaeus were studied by histological and histochemical methods and SDS-PAGE electrophoresis.The types and distribution of mucous cells on surface and alimentary tract were observed and analyzed by the methods of ABPAS. Based on the observation the mucous cells are divided into four types: type I, pure red, PAS positive and AB negative, the mucous cells include neutral mucopolysaccharide; type II, pure blue, PAS negative and AB positive, the mucous cells include acid mucopolysaccharide; type III, PAS positive more than AB, the mucous cell include mixed mucopolysaccharide; type IV, AB positive more than PAS, the mucous cells include mixed mucopolysaccharide. The results show that the mucous cells exist in the surface and alimentary, but the types and densily of mucous cells vary in different parts.There are a large amount of mucous cells on surface, such as the mantle, gill, foot, siphon and body wall, and the mucous cells mostly exist in epidermis and connective tissue. The type of mucous cells of body wall is mainly type II. The types of mucous cells of the mantle are type I, type II, type III, type IV, mostly distributing in mantle margin and three folds of mantle margin. The part of mantle central region has a small quantity of mucous cells. The types of the mucous cells of siphon are type II, type III, type IV. There are more mucous cells in the part of distant cavity than those in the other parts. There are less mucous cells on gill, and the mucous cells mostly exist in the interfilament junction and interlamellar junction. The types of the mucous cells of gill are type II. type IV. There are large amounts of mucous cells in foot. The types of mucous cells of foot are type II, type III, and typeIV.The number of mucous cells of alimentary tract is less than that of the surface. The mucous cells exist in epidermis. There are a small quantity of mucous cells inlabellum, and most of them exist in the ruga part. The types of the mucous cells are type II, type IV. There are more mucous cells in stomach than labellum, and the distribution of the mucous cells is dispersed. The mucous cells in intestines increase dramatically. Most of the mucous cells lie in the rectum, and the types of them are typen.By the studies of histochemistry, we found that the mucus includes neutral mucopolysaccharide, and acid mucopolysacchande that includes sulphate mucopolysaccharide and carbonic mucopolysaccharide. The mucous cells have ACP and AKP activity.The composition of mucus was studied by SDS-PAGE electrophoresis. The results show that the mucus included a lot of protein. A series of prominent bands are detected at 107KDa, 103Kda, 96Kda, 73KDa, 64KDa, 52KDa, 45KDa, 42KDa, 27KDa, 24.5KDa. The band at 64KDa is more obvious, with the study of the sample got from the unit with more mucus.