Evidence for reduced nitric oxide synthase (NOS) activity in the ipsilateral medial vestibular nucleus and bilateral prepositus hypoglossi following unilateral vestibular deafferentation in the guinea pig.
The aim of the present study was to examine, using a radioenzymatic assay technique, nitric oxide synthase (NOS) activity in the bilateral medial vestibular nuclei (MVN) and prepositus hypoglossi (PH), during the development of vestibular compensation for unilateral vestibular deafferentation (UVD) in the guinea pig. In the MVN ipsilateral to the UVD, and bilaterally in PH, NOS activity decreased following UVD compared to sham controls and did not recover significantly up to 50 h later, when a substantial degree of behavioural vestibular compensation had occurred. These results suggest that UVD causes a decrease in NOS activity in the ipsilateral MVN and the bilateral PH, and that a consequent decrease in NO may be responsible for some of the ocular motor and postural symptoms of UVD.
Anderson
T V
TV
Dept. of Pharmacology, School of Medical Sciences, University of Otago Medical School, Dunedin, New Zealand.
Moulton
A R
AR
Sansom
A J
AJ
Kerr
D R
DR
Laverty
R
R
Darlington
C L
CL
Smith
P F
PF
D000818:Animals; D003714:Denervation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007839:Functional Laterality / Q000502:physiology; D006168:Guinea Pigs; D007002:Hypoglossal Nerve / Q000187:drug effects / Q000201:enzymology*; D007150:Immunohistochemistry; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014726:Vestibular Nuclei / Q000187:drug effects / Q000201:enzymology*; D014722:Vestibule, Labyrinth / Q000187:drug effects / Q000294:innervation* / Q000502:physiology
D004791:Enzyme Inhibitors; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester