Cannabinoid CB2 receptor expression in the rat brainstem cochlear and vestibular nuclei.
CONCLUSIONS
This evidence suggests that both CB1 and CB2 receptors are important in the control of balance and hearing.


OBJECTIVE
Although the cannabinoid CB1 receptor has been identified in the brainstem vestibular and cochlear nuclei, the existence of the second cannabinoid receptor subtype, the CB2 receptor, has been more controversial. The aim of this study was to determine whether or not CB2 receptors are expressed in the vestibular and cochlear nuclei.


METHODS
Data were obtained from four young male Wistar rats In analyzing the presence of CB2 receptors in the vestibular and cochlear nuclei, the immunohistochemical complex was visualized by exposure to diaminobenzidine for 20 min. Positive immunoreactivity to CB2 was expressed as brown staining in the cytoplasm, nucleus, nuclear membrane and cell membrane.


RESULTS
We confirmed the existence of the CB2 receptor in the vestibular and cochlear nuclei in the brainstem of Wistar rats.
Baek
Jean-Ha
JH
Department of Pharmacology and Toxicology, School of Medical Sciences, University of Otago, Dunedin, New Zealand.
Zheng
Yiwen
Y
Darlington
Cynthia L
CL
Smith
Paul F
PF
D000818:Animals; D002831:Choroid Plexus / Q000378:metabolism; D017626:Cochlear Nucleus / Q000378:metabolism*; D020546:Fourth Ventricle / Q000378:metabolism; D008297:Male; D004856:Postural Balance / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D043885:Receptor, Cannabinoid, CB2 / Q000378:metabolism*; D014726:Vestibular Nuclei / Q000378:metabolism*
C469526:Cnr2 protein, rat; D043885:Receptor, Cannabinoid, CB2