Light and Electron Microscopic Studies on papillae of Rat Tongue in Response to Ingestion of Red Chilli

Abstract

Capsaicin is the active component responsible for hotness of red chilli. Present study evaluated effect of capsaicin contained in red chilli on rat tongue papillae. Wild rats (Rattus rattus) were fed on food containing 2% red chilli powder for a total of 7 days. Rats of control group were fed on plain food. Tissue samples of treated and untreated rats collected from the apex and body of the tongue were processed for light and scanning electron microscopic study. Light microscopy revealed tongue lined with keratinized stratified squamous epithelium which possessed numerous cylindrical filiform papillae and a few mushroom shaped fungiform papillae in untreated rats. Scanning electron microscopy revealed three different types of filiform papillae based on their tip as pointed, cylindrical and blunt. These papillae showed micropits and ridges. In rats which were sacrificed immediately after ingestion of treated bait, showed degeneration and hyperkeratization of lingual papillae with epithelium sloughed off at places. The number of micropits and ridges were more in treated rats. In rats sacrificed after 5-6 days of ingestion of treated bait, regeneration of the epithelium and lingual papillae was observed. Studies thus revealed reversible effect of capsaicin in altering histomorphology of rat tongue papillae.