Localisation of the nitric oxide (NO)/cGMP-pathway in the vestibular system of guinea pigs.
The exact distribution of nitric oxide-synthases (NOS) in the vestibular system has not been described satisfying yet. Immunostaining, using specific antibodies to the three known NOS-isoforms, to cyclic guanosine monophosphate (cGMP) and soluble guanylyl-cyclase (sGC), the second messenger system of nitric oxide (NO), was performed on paraffin sections of temporal bone from guinea pigs. eNOS could be detected in vestibular ganglion cells and in nerve fibres, including the calyces, surrounding the type 1 hair cells (HC). bNOS was found in the sensory epithelium, ganglion cells and in bone, while iNOS could not be found. NOS-detection was accompanied by reactivity to sGC and to cGMP. This finding implies that b- and eNOS-generated NO is involved in regulative processes in neurotransmission and regulation of blood flow.
Hess
A
A
Department of Oto-Rhino-Laryngology, University of Cologne, Germany.
Bloch
W
W
Su
J
J
Stennert
E
E
Addicks
K
K
Michel
O
O
D000818:Animals; D006152:Cyclic GMP / Q000502:physiology*; D005260:Female; D006162:Guanylate Cyclase / Q000378:metabolism; D006168:Guinea Pigs; D018069:Hair Cells, Vestibular / Q000201:enzymology; D007527:Isoenzymes / Q000378:metabolism; D009412:Nerve Fibers / Q000201:enzymology; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D015290:Second Messenger Systems / Q000502:physiology; D012995:Solubility; D013701:Temporal Bone / Q000201:enzymology / Q000648:ultrastructure; D014722:Vestibule, Labyrinth / Q000201:enzymology / Q000294:innervation / Q000502:physiology*
D007527:Isoenzymes; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D006162:Guanylate Cyclase; D006152:Cyclic GMP