Functional role of V form distribution seen in microvascular cast specimens of the filiform and fungiform papillae on the posterior central dorsal surface of the cat tongue

Summary The relationship between the functional role and three-dimensional structures of the microvascular network of the filiform papillae (FiP) and fungiform papillae (FuP) on the posterior central surface of the cat tongue were observed by the corrosion cast method under a scanning electron microscope (SEM). FiP can be classified into five types; types I–V (Ojima and Lowe 1995), and FuP, found to be distributed sporadically among FiP (I–V), into four types; types I–IV (Ojima et al. 1996 b) according to the shape and size of the main process (MP) and the number of the accessory processes (AP). Each of the types I–V of FiP were arranged in the form of a V as oblique lines running in an orderly and geometrical fashion from the posterior central zone to the anterior peripheral zone in both directions. Each of the types I–IV of FuP were scattered throughout the line of FiPs arranged in the form of a V, the point of which is directed towards the pharynx. FiPs play an important role in the drinking of milk and water, holding, masticating and swallowing the food and, after mixing the food with saliva, in the transporting of the food mass towards the pharynx. The MP of FuPs is considered to be a modified form of the MP of FiP of the cat tongue function (Ojima et al. 1996 c) as part of a sense organ for taste.