The effects of anti-nerve growth factor on retrograde labelling of superior cervical ganglion neurones projecting to the molar pulp in the rat.
The aims were to demonstrate sympathetic ganglion neurones projecting to the rat molar pulp and to determine whether deprivation of nerve growth factor (NGF) in neonatal rats eliminates this source of pulpal innervation. Newborn Sprague-Dawley rats were given subcutaneous injections of rabbit anti-mouse-NGF serum for 1 month. Control animals included litter mates treated with preimmune serum and untreated, age-matched rats. AT 4 months of age, Fluoro-gold (FG) was applied to the pulp chamber of the right first maxillary molar. One week later, the animals were perfusion fixed, and the superior cervical ganglia (SCG) were removed, embedded in paraffin, and serially sectioned at 10 microns. FG-labelled cells were detected by epifluorescence microscopy with a u.v. filter set. Control animals had 5-10 FG-labelled neurones widely distributed throughout the SCG ipsilateral to the injection site and no labelled cells in the contralateral SCG. NGF-deprived animals had either no FG-labelled cells or a single labelled cell in the ipsilateral SCG. These results indicate that, in rats, (1) the number of SCG neurones projecting to the molar pulp is rather low, (2) SCG neurones that innervate the dental pulp of the maxillary molar pulp are dispersed throughout the ganglion, (3) the projection from SCG to the molar is exclusively ipsilateral, and (4) neonatal NGF deprivation induces a permanent, almost total, loss of sympathetic neurones projecting to the dental pulp.
Qian
X B
XB
Department of Anatomy, University of Mississippi Medical Center, Jackson 39216, USA.
Naftel
J P
JP
D000818:Animals; D000831:Animals, Newborn; D000906:Antibodies; D001369:Axons / Q000502:physiology; D003782:Dental Pulp / Q000294:innervation*; D005260:Female; D005456:Fluorescent Dyes; D005728:Ganglia, Sympathetic / Q000166:cytology*; D007150:Immunohistochemistry; D008297:Male; D008437:Maxilla; D008856:Microscopy, Fluorescence; D008963:Molar / Q000294:innervation; D009333:Neck; D009414:Nerve Growth Factors / Q000172:deficiency / Q000502:physiology*; D009475:Neurons, Afferent / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013266:Stilbamidines
C049774:2-hydroxy-4,4'-diamidinostilbene, methanesulfonate salt; D000906:Antibodies; D005456:Fluorescent Dyes; D009414:Nerve Growth Factors; D013266:Stilbamidines