Disease relevance of Efferent Pathways

• Further analyses will determine whether other hereditary disorders with primitive involvement of the central motor pathways, as pure forms of spastic paraplegia, could be due to alsin dysfunction [1].
• The NADPH diaphorase histochemical reaction was used in combination with retrograde axonal transport of Fluorogold (FG) from the major pelvic ganglion (MPG) to determine if NADPH diaphorase is contained within afferent and preganglionic efferent pathways to pelvic visceral organs [2].
• The adenosine A2a receptor localization to striatopallidal neurons suggests that a selective activation of the striatopallidal efferent pathway is involved in the expression of catalepsy induced by intrastriatal infusion of CGS 21680C [3].
• Parkinson's disease (PD), a hypokinetic disorder, and Huntington's disease (HD), a hyperkinetic disorder, share the fact that in the motor pathways the dysfunction starts in the striatum [4].
• We used magnetic cortical stimulation (a painless alternative to electrocortical stimulation) and F-wave analysis to study conduction in the central and peripheral motor pathways in 18 HTLV-I seropositive, Jamaican TSP patients (ages 29-70 years; duration of symptoms 3-20 years) and 22 normal controls [5].

High impact information on Efferent Pathways

• These effects are discussed in light of recent studies suggesting that dopamine, acting on D1 and D2 dopamine receptor subtypes, activates distinct efferent pathways from the striatum [6].
• We propose that imbalance between dynorphin and substance P release from the same striatonigral motor efferent pathway, related to D3 receptor induction, is responsible for behavioral sensitization [7].
• The stimulation of these neurons activates efferent pathways which induce the release of ANP [8].
• The results suggest that the caudate-putamen and its gamma-aminobutyrate-dependent efferent pathways modulate the threshold for seizures in the limbic forebrain [9].
• We conclude that left atrial distention reflexly reduces the rates of renin secretion via vagal afferent and renal sympathetic efferent pathways [10].

Chemical compound and disease context of Efferent Pathways

• In P14-17 rats stimulation of neurones in either the solitary tract or ambiguual nuclei, by microinjection of L-glutamate (100-200 pmol), evoked an atropine-sensitive bradycardia indicating a functional integrity of central and peripheral efferent pathways mediating the baroreceptor reflex [11].
• In the cooperative patient the crossed extensor response is a more sensitive indicator of a minor disturbance within the cortico-spinal motor pathways than the Babinski sign [12].

Biological context of Efferent Pathways

• Furthermore, [corrected] potentials evoked by transcranial magnetic stimulation (MEP) were compared with those evoked by cervical or lumbosacral electrical stimulation and often revealed marked slowing of transmission in central motor pathways [13].
• These results highlight the role of the modulation of gene expression in adaptive processes to dopamine deficiency in striatal efferent pathways [14].
• It is concluded that methanandamide depresses intestinal peristalsis via activation of CB1 receptors on enteric neurons, which results in blockade of excitatory motor pathways and facilitation of inhibitory pathways operating via apamin-sensitive K+ channels and nitric oxide [15].
• OBJECTIVES: To improve the diagnosis of damaged spinal motor pathways in incomplete spinal cord injury (iSCI) by assessing the facilitation of lower limbs motor evoked potentials (MEP).METHODS: Control subjects (n = 12) and iSCI patients (n = 21) performed static and dynamic isometric foot dorsiflexions [16].
• Neuroanatomy, neurophysiology, and central auditory assessment. Part III: Corpus callosum and efferent pathways [17].

Anatomical context of Efferent Pathways

• The expression of substance P and methionine-enkephalin, which are involved in the efferent pathways in the basal ganglia, in the globus pallidus and substantia nigra was spared [18].
• We propose a "working" glutamate hypothesis of schizophrenia which postulates a diminished glutamatergic transmission in the hippocampal glutamate-mediated efferent pathways and cerebral dysfunction in the hippocampus and its target areas, especially the anterior cingulate cortex [19].
• CONCLUSIONS: Intrathecal bupivacaine has no selectivity for the afferent and efferent pathways, and intrathecal fentanyl acts synergistically to enhance the effect of bupivacaine on the afferent pathway without a measurable effect on sympathetic outflow [20].
• The data suggest that basal ganglia output under conditions of increased dopamine receptor stimulation is influenced by the activation of excitatory subthalamic efferent pathways, as opposed to suppression of these pathways as predicted by current models of basal ganglia function [21].
• One of the major efferent pathways of the superior colliculus crosses midline to run caudally in the contralateral predorsal bundle, innervating targets in the brain stem and eventually reaching the cervical spinal cord [22].

Associations of Efferent Pathways with chemical compounds

• We report that the GABAergic striopallidal neuron, which is a key component of the indirect striatal efferent pathway, is a main locus for A2-D2 interactions in the brain and possibly a main target for the central actions of adenosine agonists and antagonists [23].
• The ability to DNFB tolerant cells to block afferent sensitization pathways differs from the mechanism of tolerance to picryl chloride, reported by others, where efferent pathways are blocked [24].
• Octreotide was shown to reduce the perception of rectal distension without affecting motor pathways or local rectal reflexes [25].
• This suggests a similarity in the pattern of neuronal activity evoked by PGE1 and leucocyte pyrogen, at least at the site(s) where atropine directly or indirectly exerted its effect and in the efferent pathways from this site [26].
• Specific enhancement by fentanyl of the effects of intrathecal bupivacaine on nociceptive afferent but not on sympathetic efferent pathways in dogs [20].

Gene context of Efferent Pathways

• These include genes whose products act in two spindle motor pathways that overlap in function with Cin8p, the kinesin-related Kip1p pathway and the cytoplasmic dynein pathway [27].
• The present study suggests that orexin-containing neurons in the perifornical area play a role as one of the efferent pathways of defense response and also operate as a regulator of AP at basal condition by activating sympathetic outflow [28].
• This action depends not only on a direct activation of the muscle through NK1 and/or NK2 receptors, but also on stimulation of excitatory enteric motor pathways through NK3 and/or NK1 receptors [29].
• The substance P-containing striatal efferent pathway was more resistant to the HD mutation than met-enkephalin-producing striatal projection neurons in the transgenics, based on neuropeptide immunofluorescent staining [30].
• We report that NR2A and NR2B mRNA levels did not change within the anterior forebrain or vocal motor pathways after adult deafening, even after substantial changes in song structure [31].

Analytical, diagnostic and therapeutic context of Efferent Pathways

• EEG and serum prolactin studies in relation to transcutaneous stimulation of central motor pathways [32].
• Several studies using transcranial magnetic stimulation demonstrated functional integrity of the efferent pathways from the right M1, intact sensory afferents to M1, an impairment of transcallosal connection between the bilateral motor cortices, and reduced ipsilateral cortico-cortical inhibition within the right M1 [33].
• BACKGROUND: Tropical Spastic Paraparesis/HTLV-I Associated Myelopathy (HAM/TSP) is a chronic, progressive myelopathy endemic to the Caribbean. In HAM/TSP, peripheral motor pathways have been assessed using electromyography and nerve conduction studies; central motor pathways have been assessed to a limited extent using electrocortical stimulation [5].
• We conclude that the central IOP-lowering effect of clonidine is diminished after cervical sympathectomy, indicating that the peripheral sympathetic nervous system is the efferent pathway of this centrally initiated effect [34].
• To characterize the efferent pathways involved in these reflexes, we have studied the emptying of liquid test meals in control rats and in rats after celiac ganglionectomy, pyloroplasty, and treatment with guanethidine or 6-hydroxydopamine, and in rats with circulating vasoactive intestinal polypeptide (VIP) antibodies [35].

References