Richard N. Ranson

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BACKGROUND Age-associated myenteric neuronal loss has been described in several species. In some studies,cholinergic neurons have been reported to be selectively vulnerable, whereas nitrergic neurons are spared. Aging of the mouse enteric nervous system(ENS) and the subtypes of mouse myenteric neurons that may be lost have been little studied. We therefore(More)
Age-related changes in the number and size of large cholinergic terminals immunoreactive for vesicular acetylcholine transporter (VAChT), were documented for the dorsolateral nucleus (DLN), retrodorsolateral nucleus (RDLN) and spinal nucleus of the bulbospongiosus (SNB) of the lumbosacral spinal cord of male rats. The most significant changes were a large(More)
BACKGROUND The innervation of the mouse internal anal sphincter (IAS) has been little studied, and how it changes during aging has not previously been investigated. The aim of this study was therefore to characterize the distribution and density of subtypes of nerve fibers in the IAS and underlying mucosa in 3-, 12- to 13-, 18- and 24- to 25-month-old male(More)
We have analysed age-related changes in the morphology of preganglionic neurones in the lumbosacral spinal cord, labelled following injection of retrograde tracers into the major pelvic ganglion of young adult and aged male rats. We have also examined changes in neurotransmitter-characterised spinal afferent inputs to these neurones, or to the nuclei in(More)
The immunocytochemical localisation of vesicular glutamate transporters, VGLUT1 and VGLUT2, was employed to identify putative glutamatergic axon terminals innervating pelvic motoneurons. VGLUT1 terminals were sparsely distributed within lumbosacral spinal motoneuron pools, including the dorsolateral nucleus, retrodorsolateral nucleus and spinal nucleus of(More)
Quantitative image analysis was used to determine age-related changes in the substance P-containing innervation of autonomic and somatic nuclei in the lumbosacral spinal cord, which are associated with the control of micturition and sexual reflexes. In the upper lumbar segments (L1-L2), significant declines in the distribution density of substance(More)
In the rat, the neurochemical phenotypes of neurons that are presynaptic to motoneurons innervating the levator ani are poorly defined. In this study, motoneurons within the spinal nucleus of the bulbospongiosus (SNB) were revealed, using retrograde labelling, following injection of cholera toxin B subunit into the levator ani muscle. Different classes of(More)
This study sought to determine the effects of ageing on the in vivo micturition characteristics of male Wistar rats and to assess whether they might be replicated in young rats by using the neurotoxin DSP-4 to lesion locus coeruleus-derived noradrenergic pathways projecting to spinal cord nuclei controlling micturition. Significant age-related changes in(More)
Using a combination of anterograde and retrograde neuronal tract-tracing techniques, the descending projections from the paraventricular nucleus of the hypothalamus (PVN) to the brain/spinal cord and in particular those axonal projections that appear to be contiguous with sympathetic preganglionic neurones (SPN) projecting to the stellate ganglion have been(More)
The effects of ageing on the innervation patterns of lumbosacral spinal nuclei involved in controlling lower urinary tract functions, including micturition, were studied using immunohistochemistry for serotonin (5-HT) and tyrosine hydroxylase (TH) in male Wistar rats of 3 and 24 months. Quantitative image analysis revealed significant age-associated(More)