geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Descending pathways eliciting forelimb stepping in the lateral funiculus experimental studies with stimulation and lesion of the cervical cord in decerebrate cats


, : Descending pathways eliciting forelimb stepping in the lateral funiculus experimental studies with stimulation and lesion of the cervical cord in decerebrate cats. Brain Research 379(1): 125-136

The funicular pathways that elicit forelimb stepping were investigated with stimulation and lesion of the cervical white matter in decerebrate cats with the lower thoracic cord transected. We localized cross-sectional areas where stimulation evoked rhythmic motor-nerve discharge imitating those of stepping (fictive locomotion) in the immobilized animal, and further examined whether or not lesions made in the corresponding areas abolished actual locomotor movements. Stimulation of the C3 lateral funiculus (LF) produced fictive locomotion in the ipsilateral forelimb. The effective areas of stimulation were located separately in the dorsolateral funiculus (DLF) and in the ventrolateral funiculus (VLF), while the VLF was more effective than the DLF. Effective stimuli were pulse trains with a frequency of about 30 Hz, with a rather wide pulse duration of about 0.5 ms. Blocking axonal conduction through the lower thoracic cord by cooling reproducibly facilitated fictive locomotion in both amplitude and frequency. In the lesion experiments, forelimb locomotor movements were elicited spontaneously or by stimulation of the mesencephalic locomotor region (MLR). The locomotor movements were abolished by complete lesions of the C2-C3 LFs on both sides, but these remained when either the DLF or the VLF was intact on one side. These findings together suggested that the descending pathways for the activation of the spinal locomotor network of the single forelimb are located ipsilaterally in the DLF as well as in the VLF. Both the DLF and the VLF pathways can initiate locomotion, while the VLF pathways have a higher potential for its initiation. Lesion experiments further showed that cats can walk with both forelimbs, even though the spinal locomotor network of the single forelimb was deprived of its main descending input by unilateral lesions of the LF. However, when the unilateral lesion extended to the medial part of the LF, the bilateral walking was abolished; the limb on the lesioned side showed only rhythmic extension movements without active flexion movements, which was out of phase with the stepping movements on the intact side. This finding suggested that the medial part of the LF is important for producing flexion movements during the swing phase of stepping.

US$19.90

PMID: 3742207

DOI: 10.1016/0006-8993(86)90264-7


Other references

Ferchichi, L.; Kourda, N.; Zermani, R.; Aouem, J.; Zaouche, A.; Abdjellil, Z.; Najah, N.; Baltagi Ben Jilani, S., 2006: Extragastrointestinal stromal tumors: a report of 4 cases. Gastrointestinal stromal tumors (GIST) are mesenchymal tumors that arise from the wall of the gastrointestinal tract expressing CD117 and/or the CD34. Similar tumors were described in the soft tissue of the abdomen and are so-called extragastroint...

Grembergen, G.Van, 1949: Le metabolisme respiratoire du trematode Fasdola hepatica Linn., 1758. Van Grembergen, studying the respiratory mechanism of Fasdola hepatica finds that his results differ only quantitatively from those obtained for Moniezia benedeni. He does not agree with the results obtained by Harnisch. Oxygen consumption of both...

Omokhodion, F.O.; Adeosun, A.A.; Fajola, A.A., 2007: Hearing impairment among mill workers in small scale enterprises in southwest Nigeria. This cross-sectional study was conducted among mill workers in a large market in Ibadan, southwest Nigeria. These workers are engaged in small scale businesses with little or no regulation of work exposures. Questionnaires administered to mill wor...

Mattern, D.L., 1990: Stearolic acid lengthens the condition period of Neurospora crassa carrying the cel mutation. Progress in Clinical and Biological Research 341b: 253-262

Ramos, R., M.A.; Siciliano, S.; Borobia, M.; Zerbini, A., N.; Pizzorno, J.-Luis, A.; Fragoso, A.-Bernadete, L.; Lailson-Brito, J.,. Jr.;; De-Freitas-Azevedo, A.; Simoes-Lopes, P.-Cesar; De-Oliveira-Santos, M.-Cesar, 2001: A note on strandings and age of sperm whales (Physeter macrocephalus) on the Brazilian coast. This note compiles recorded strandings of sperm whales on the Brazilian coast. A known total of 95 sperm whales (62 single and one mass stranding of 33 individuals) stranded along the Brazilian coast from 1967-2000. A higher incidence of single st...

Azimi-Garakani, C.; Beardmore, J.A., 1989: Tongue-rolling phenotypes and geographical variation in the United Kingdom. The distribution of tongue-rolling phenotypes in a sample (n = 477) of undergraduate students of the University College of Swansea (U.K.) was studied. The birthplaces of these students were also recorded. England was divided into six areas, and Wa...

Okada Y.; Yamaguchi T., 1989: Response properties of nonspiking giant interneurons in the crayfish brain. Zoological Science (Tokyo) 6(6): 1074

Simopoulos, A.P., 2014: Dietary omega-3 fatty acid deficiency and high fructose intake in the development of metabolic syndrome, brain metabolic abnormalities, and non-alcoholic fatty liver disease. Western diets are characterized by both dietary omega-3 fatty acid deficiency and increased fructose intake. The latter found in high amounts in added sugars such as sucrose and high fructose corn syrup (HFCS). Both a low intake of omega-3 fatty a...

Bodig, J., 1968: Transverse mechanical properties of Douglas Fir treated with organic liquids. I. Dimensional changes. II. Compression properties. (I) Previous work on the effects of liquids on the dimensions of wood is reviewed and results are given of experiments with 19 organic liquids on the radial and tangential dimensions of 12 small blocks of green wood (on which little previous work...

Afzali, A.Maisam.; Ruck, T.; Wiendl, H.; Meuth, S.G., 2017: Animal models in idiopathic inflammatory myopathies: How to overcome a translational roadblock?. Idiopathic inflammatory myopathies (IIMs) encompass a heterogenic group of rare muscle diseases with common symptoms including muscle weakness and the presence of certain histological features. Since the pathogenesis remains unclear, therapeutic a...