Effects of neonatal exposure to anti-nerve growth factor on the number and size distribution of trigeminal neurones projecting to the molar dental pulp in rats

摘要: Abstract The first aim of the present study was to determine whether depletion endogenous nerve growth factor (NGF) during early postnatal development results in a long-term deficit number trigeminal ganglion cells and axons projecting molar pulp. second identify selectivity effects NGF deprivation for any specific size group among pulp neurones. Newborn Sprague-Dawley rats were given subcutaneous injections either rabbit anti-mouse-NGF serum or non-immune (control) period 1 month. At age 4 months, Fluoro-gold (FG) applied chamber right maxillary molar. One week later, animals perfusion-fixed, ganglia removed serially sectioned with cryostat. Labelled neurones seen only ipsilateral injected teeth. area every labelled cell profile measured, from these data, estimates true distribution FG-labelled obtained by recursive translation. Ganglia control had mean 197 neurones, all division, most somas medium large diameter. NGF-deprived significantly fewer (mean = 145) tooth. Neurones less than 30 μm dia strikingly subnormal anti-NGF treated (64% controls). In accordance greater susceptibility small exposure, deficits apical fibres mandibular degree duration unmyelinated myelinated axons. It is concluded that an important mediator regulation sensory innervation dental also indicate at least one class larger pulpal afferent regulated factors other NGF.