Localisation of cannabinoid receptor 1 in rat dorsal root ganglion using in situ hybridisation and immunohistochemistry.
In this study we used in situ hybridisation and double-labelling immunohistochemistry to characterise cannabinoid receptor 1 (CB(1)) expression in rat lumbar dorsal root ganglion (DRG) neurons.Approximately 25% of DRG neurons expressed CB(1) mRNA and displayed immunoreactivity for CB(1). Sixty-nine percent to 82% of CB(1)-expressing cells were also immunoreactive for neurofilament 200, indicative of myelinated A-fibre neurons, which tend to be large- and medium-sized DRG neurons (>600 microm(2)). Approximately 10% of CB1-expressing cells also expressed transient receptor potential vanilloid family ion channel 2 (TRPV2), the noxious heat-transducing channel found in medium to large lightly myelinated Adelta-fibre DRG neurons. Seventeen percent to 26% of CB(1)-expressing cells co-stained using Isolectin B4, 9-10% for calcitonin gene-related peptide and 11-20% for transient receptor potential vanilloid family ion channel 1 (TRPV1), predominantly markers of small non-myelinated C-fibre DRG neurons (<600 microm(2)). These findings suggest that whilst a wide range of DRG neuron phenotypes express CB(1), it is predominantly associated with myelinated fibres.
Bridges
D
D
Pain Research, Department of Anaesthetics, Faculty of Medicine, Imperial College, Chelsea and Westminster Hospital Campus, London, UK.
Rice
A S C
AS
Egertová
M
M
Elphick
M R
MR
Winter
J
J
Michael
G J
GJ
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D048429:Cell Size / Q000502:physiology; D005455:Fluorescent Antibody Technique; D005727:Ganglia, Spinal / Q000166:cytology / Q000378:metabolism*; D006023:Glycoproteins; D037102:Lectins / Q000378:metabolism; D008297:Male; D008465:Mechanoreceptors / Q000166:cytology / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D009413:Nerve Fibers, Myelinated / Q000378:metabolism* / Q000648:ultrastructure; D036421:Nerve Fibers, Unmyelinated / Q000378:metabolism* / Q000648:ultrastructure; D016900:Neurofilament Proteins / Q000378:metabolism; D009475:Neurons, Afferent / Q000166:cytology / Q000378:metabolism*; D009619:Nociceptors / Q000166:cytology / Q000378:metabolism*; D010146:Pain / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug / Q000235:genetics* / Q000378:metabolism
D006023:Glycoproteins; D037102:Lectins; D016900:Neurofilament Proteins; D012333:RNA, Messenger; D043882:Receptors, Cannabinoid; D011955:Receptors, Drug; C473590:isolectin B4-binding glycoprotein, mouse; C051774:neurofilament protein H; D015740:Calcitonin Gene-Related Peptide