To verify the postoperative ultrastructural changes of the myotendinous nerve endings of feline extraocular muscles, which are known as proprioceptors. Sixteen recti of four cats were used and divided into three groups. In group A, eight lateral recti were recessed. In group B, four medial recti were resected by 10 mm from insertion to include the myotendinous junction. In group C, four medial recti were resected by 4 mm of muscle bellies only, without disturbing the myotendinous junction. Four weeks after surgery, specimens were examined with electron microscopy. In group A, overall neural structures were well maintained with slight axonal degeneration. In group B, only muscle fibers were observed without any regeneration of neural sprouts. In group C, axonal disintegration and shrinkage were evident. These results indicate that myotendinous nerve endings can be damaged in strabismus surgery, and that resection was more invasive than recession in disrupting myotendinous nerve endings.
Animals ; Cats ; Motor Neurons/ultrastructure ; Nerve Endings/*ultrastructure ; Neuromuscular Junction/*ultrastructure ; Oculomotor Muscles/*innervation/surgery ; Oculomotor Nerve/*ultrastructure ; *Ophthalmologic Surgical Procedures ; Receptors, Sensory/ultrastructure ; Strabismus/surgery ; Tendons/*innervation/ultrastructure

OBJECTIVETo investigate the role of ICC-like cells in bladder neuromodulation in rat urinary bladder.

METHODS14 SD rats and 1 guinea pig were sacrificed in this study. The ultra structural relationships among interstitial cells, nerves and detrusor smooth muscle cells (DSMCs) of urinary bladder were investigated by transmission electron microscopy (TEM). c-kit immunofluorescence was used to identify ICC-like cells in SD rat urinary bladder and the structural relationship between ICC-like cells and nerve terminals was studied by immunofluorescence (double-label).

RESULTSGap junction between ICC-like cells and DSMCs was confirmed by TEM. ICC-like cells were very close apposition with nerve terminals under TEM. ICC-like cells were identified to exist in sub-urothelium layer, along the longitude of smooth muscle bundles and among detrusor smooth muscle in SD rat urinary bladder by c-kit immunofluorescence. Double-labeled tissue with c-kit and PGP9.5 antibodies also showed that ICC-like cells were very close apposition with nerve terminals in SD rat bladder.

CONCLUSIONSMorphological study indicated that ICC-like cells in rat urinary bladder may play an important role in detrusor neuromodulation. Further study on function will be helpful for elucidating the mechanism of bladder neuromodulation clearly.

Animals ; Cells, Cultured ; Female ; Gap Junctions ; Guinea Pigs ; Male ; Muscle, Smooth ; innervation ; Myocytes, Smooth Muscle ; cytology ; ultrastructure ; Nerve Endings ; ultrastructure ; Rats ; Rats, Sprague-Dawley ; Urinary Bladder ; cytology ; innervation ; ultrastructure