Functional role and angioarchitectural arrangement of the filiform and fungiform papillae on the medial-dorsal surface of the beagle dog tongue.

A scanning electron microscopic study has been performed on the three-dimensional morphological structure and functional arrangement in microvascular cast specimens (MVCS) of the filiform (FiP) and fungiform papillae (FuP) of the entire medial-dorsal surface of the caudal portion of the beagle dog tongue. The characteristics and functional arrangements of each FiP and FuP were as follows: The FiPs densely and geometrically covered the entire medial-dorsal surface. The outer structure of the FiPs was composed of both the main process (mp) and accessory process (ap). These were formed by both the ascending and descending branches and originating in their tributaries was a spoon-like capillary micronetwork structure with a sharp arrowhead-like top. The mp inclined posteriorly and the ap anteriorly. On the other hand, the outer structure of the FuPs was a rounded papillary body composed of a capillary microvascular network consisting of the ascending and descending branches just as the FiPs. They were distributed sporadically along the oblique eines of FiPs in a V running from both peripheral edges in the posterocentral direction. It has been conjectured that the FiPs play a concentric functionally important role in transporting food and liquid from both the peripheral edges to the postero-central part or towards the pharynx, and on the other hand the FuPs play an assisting role in receiving gustatory sensations from the masticated food and liquid on the medial-peripheral and central-dorsal surface of the caudal portion of the beagle dog tongue.