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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Female, Gene Expression Regulation, Developmental, Pregnancy, RNA, Messenger, Rats, Receptors, Retinoic Acid, Retinoic Acid Receptor alpha, Reverse Transcriptase Polymerase Chain Reaction, Vitamin A, Vitamin A Deficiency, Vitamins, Vocal Cords.
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Does roles of vitamin A and macula flava in maintaining vocal fold? Context: Vitamin A plays important roles in development, growth, and regeneration. Vitamin A-storing stellate cells have been identified in several organs. The functional roles of vitamin A in the vocal folds are still unknown, although vitamin A-storing vocal fold stellate cells have been observed in the macula flava of human and rat vocal folds. The purpose of this study was to investigate the roles of vitamin A in vocal folds. Vitamin A-deficient rats were generated, and the vocal folds were examined histologically. Messenger RNA was extracted from the vocal folds and analyzed by real-time polymerase chain reaction. Immunohistochemical analysis of normal vocal folds revealed expression of retinoic acid receptor a in vocal fold stellate cells. The cells in the macula flava of vitamin A-deficient rats showed a larger nucleus/cytoplasm ratio than did those of vitamin A-sufficient rats, but messenger RNA expression of major extracellular matrix components in the macula flava of vitamin A-deficient rats did not present a remarkable change except for procollagen type I. Expression of hyaluronic acid, collagen types I and III, and elastin did not show a significant change in vitamin A-deficient rat vocal folds.
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These results indicate that vitamin A is not essential to maintaining the extracellular matrix of normal adult vocal folds, although vocal fold stellate cells participate in vitamin A storage. Final Decision: yes