Substance P-containing axon terminals in the mucosa of the human urinary bladder: pre-embedding immunohistochemistry using cryostat sections for electron microscopy.
The ultrastructure of substance P (SP)-containing axon terminals in the mucosa of the human urinary bladder was studied. Numerous SP-immunoreactive varicose nerve fibers were seen in the lamina propria, and most of them ran freely in the connective tissue. Many SP-immunoreactive nerve fibers were observed beneath the epithelium, and perivascular SP-immunoreactive nerves were also found in the submucosal layer. We observed a total of 305 SP-immunoreactive (IR) axon terminals, of which most (89.6%) were free nerve endings at the ultrastructural level; the rest of the SR-IR axon terminale were seen in the vicinity of the epithelium and blood vessels in the lamina propria. Varicose regions of SP-IR axon terminals contained large granular and small agranular synaptic vesicles, and most of them partially lacked a Schwann cell sheath. In some SP-IR varicosities, synaptic vesicles were concentrated in the region without any Schwann cell sheath. Long storage (for more than 1 month) of fixed-tissue pieces in sucrose before freezing has improved the ultrastructure of cryostat sections in pre-embedding immunohistochemistry. Trypsin digestion for the purpose of exposing antigenic sites was also employed before applying the first antiserum.
Wakabayashi
Y
Y
Department of Urology, Shiga University of Medical Science, Japan.
Tomoyoshi
T
T
Fujimiya
M
M
Arai
R
R
Maeda
T
T
D000368:Aged; D001369:Axons / Q000378:metabolism* / Q000648:ultrastructure; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D016253:Microscopy, Immunoelectron; D009092:Mucous Membrane / Q000294:innervation / Q000378:metabolism / Q000648:ultrastructure; D009411:Nerve Endings / Q000378:metabolism / Q000648:ultrastructure; D013373:Substance P / Q000378:metabolism*; D001743:Urinary Bladder / Q000294:innervation* / Q000378:metabolism* / Q000648:ultrastructure
D013373:Substance P