The ultrastructure of Ruffini and Herbst corpuscles in the articular capsule of domestic pigeon

Abstract

The present study identifies two types of sensory nerve endings in the articular capsule of the shoulder joint of domestic pigeons: Ruffini corpuscles (spray-like endings), and Herbst corpuscles. Ruffini corpuscles occur in the fibrous membrane of the articular capsule and consist of two to four branched cylindrical segments within a network of fascicles of collagen fibers. At the terminal ends of the cylinders the perineural sheaths of the capsule are deficient and surround the fascicles of collagen fibers. The axon terminals in each cylindrical segment of a Ruffini corpuscle repeatedly ramify, giving rise to delicate neurite profiles. These neurites and associated Schwann cells envelope small fascicles of collagen fibrils. Schwann cells cover only a part of the neurite profiles. The myelinated afferent axon enters the midregion of the cylinder and has a diameter of approximately 3 micrometer. Herbst corpuscles are situated in the subsynovial connective tissue and in the transition zone between the fibrous membrane and the muscular fascia. They appear as elongated ovals in longitudinal section and round in cross section. Small corpuscles measure approximately 5 micrometer x 200 micrometer in length and large ones approximately 100 micrometer x 600 micrometer. Each has a myelinated afferent axon (diameter 2.5--7.5 micrometer) that terminates in one to three inner cores. The inner core contains the nonmyelinated receptor portion of the nerve fiber surrounded by numerous cytoplasmic lamellae, a subcapsular connective tissue space, and a perineural capsule of eight to 12 layers. Avian joint receptors are similar to those present in the skin of various birds and Ruffini corpuscles resemble in fine structure equivalent receptors in joint corpuscles of the domestic cat.

Electron microscope study of the grandry and herbst corpuscles in the palatine mucosa, gingival mucosa and beak skin of the duck.

“…These characteristics have also been reported by ANDRES (1969), SAXOD (1970SAXOD ( , 1978, HALATA (1971), HALATA and MUNGER (1980). In some portions of cytoplasm of lamellae, a periodic increase in density about 20 nm in width is noted, where the periodic density of neighboring sheets are aligned side by side.…”

“…W.AT.ANARF, J. USIIKURA and E. YAM.AD.A: corpuscle were described by ANDRES (1969), NAFSTAD and ANDERSEN (1970), SAXOD (1970bSAXOD ( , 1978, HALATA (1971)and HALATA and MUNGER (1980). Concerning the characteristics of the Grandry corpuscle, there have been only a few reports by SAXOD (1968, 1970a, 1978), ANDRES (1969) and IDE and MUNGER (1978).…”

The fine structure of lamellated nerve endings found in the rat gingiva.

“…QUILLIAN and ARMSTRONG (1963), ANDRES (1969), SAXOD (1970), NAFASTAD andANDERSEN (1970), HALATA (1971), HALATA and MUNGER (1980), ANDRES and DURING (1973) reported similar ultrastructural characteristics in the Herbst corpuscles.…”

Nerve endings of the wrist joint: A preliminary report of the dorsal radiocarpal ligament

“…[1][2][3][4][5][6][7] Freeman and Wyke 2,3 synthesized a number of previous reports and condensed terminology into four types (Table 1). However, modifications of this classification scheme have been subsequently introduced due to the discovery of nerve ending morphology that did not fit the original criteria.…”

“…Many studies of mechanoreceptors and nerve endings in joints other than the wrist have been published. [1][2][3][4][5][6][7] These studies, however, are typically lacking a physiologic connection between the identification of the mechanoreceptors or nerve endings and their neurophysiologic function. The wrist offers a unique anatomic situation that will enhance our ability to study the function of nerve endings.…”