Three-Dimensional Microanatomy of Mechanoreceptors and Their Possible Mechanism of Sensory Transduction

The study examined the fine structure of sensory nerve endings in rats using electron microscopy to understand mechanoreception. It focused on Ruffini endings in periodontal ligaments and lanceolate endings around sinus hairs, both featuring an axon-Schwann cell complex. Specific modifications were observed at the distal ends, where Schwann cell processes projected into tissues, interacting with axon terminals. In Ruffini endings, these structures coiled around collagen bundles, aiding in tissue distortion transmission. In lanceolate endings, Schwann cell tufts were in an amorphous matrix, with axon fingers deflecting during hair movement. The study suggested that these complexes contribute to mechano-electric transduction.