Afferent-inherent regulation of myosin heavy chain isoforms in rat muscle spindles.
Afferent Pathways/physiology; Afferent/*physiology; Animals; Denervation; Female; Ganglia; Ganglionectomy; Isomerism; Muscle Spindles/*metabolism; Myosin Heavy Chains/*metabolism; Neurons; Rats; Spinal Cord/physiology; Spinal/physiology; Sprague-Dawley; Toes/innervation
Whether afferents exert their morphogenetic influence on spindles through release of trophic factors at intrafusal fiber junctions or via participation in proprioceptive pathways which modulate the motor activity to muscles was investigated by comparing myosin heavy chain (MHC) expression in intrafusal fibers after ablation of afferents (deafferentation, or DA) to the extensor digitorum longus (EDL) of adult rats or after ablation of the corresponding central processes of afferents to the spinal cord (central-process ablation, or CPA). DA and CPA elicited an exaggerated pedal plantarflexion, and hypertrophy of the EDL concomitant with atrophy of the soleus in the affected hindlimb. Frequencies and patterns of expression of seven MHCs expressed by intrafusal fibers in CPA muscles were indistinguishable from normal rats. However, frequencies and patterns of expression of several MHCs were abnormal following DA. Thus factors transported anterogradely from afferents to intrafusal fibers may regulate MHC expression in intrafusal fibers.
Walro J M; Wang J; Story G M
Muscle & nerve
1997
1997-12
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1002/(sici)1097-4598(199712)20:12%3C1549::aid-mus10%3E3.0.co;2-w" target="_blank" rel="noreferrer noopener">10.1002/(sici)1097-4598(199712)20:12%3C1549::aid-mus10%3E3.0.co;2-w</a>
Inhibition of nerve growth factor-stimulated neurite outgrowth by methylamine-modified alpha 2-macroglobulin.
alpha-Macroglobulins/metabolism/*pharmacology; Animals; Cells; Chick Embryo; Cultured; Drug Interactions; Female; Ganglia; Humans; Male; Methylamines/*pharmacology; Mice; Nerve Growth Factors/antagonists & inhibitors/metabolism/*pharmacology; Neurites/drug effects/*physiology/ultrastructure; Neurons/cytology/physiology; Placenta; Pregnancy; Spinal/physiology; Submandibular Gland
alpha 2-Macroglobulin (alpha 2M) is a rather ubiquitous protein in extracellular spaces of mammals. It is an inhibitor of endopeptidases, can be modified by aliphatic amines, and combines with a number of hormones/cytokines such as beta-nerve growth factor (NGF) [Koo PH, Stach RW (1989): J Neurosci Res 22:247]. The objective of this study is to compare the NGF-binding properties of methylamine-modified human alpha 2M (MA-alpha 2M) versus normal alpha 2M and their effects on the biological activity of NGF and neurite extension by embryonic chicken dorsal root ganglia. As determined by gel filtration, polyacrylamide gel electrophoresis, and equilibrium binding studies, these two forms of alpha 2M are similar in their binding affinities, with MA-alpha 2M binding about twice as much NGF as normal alpha 2M. Both normal alpha 2M and
Koo P H; Liebl D J
Journal of neuroscience research
1992
1992-04
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1002/jnr.490310412" target="_blank" rel="noreferrer noopener">10.1002/jnr.490310412</a>
The role of sensory neurons in cervical ripening: effects of estrogen and neuropeptides.
Afferent/metabolism/*physiology; Cervical Ripening/*physiology; Cervix Uteri/innervation; Estrogen/physiology; Estrogens/*physiology; Female; Ganglia; Humans; Neurons; Neuropeptides/biosynthesis/*physiology; Pregnancy; Receptors; Spinal/physiology
Central nervous system nuclei and circuits, such as the medial preoptic, ventromedial and paraventricular nuclei of the hypothalamus, play important roles in reproduction and parturition, and are influenced by estrogen. Peripheral autonomic and sensory neurons also play important roles in pregnancy and parturition. Moreover, the steroid hormone estrogen acts directly, not only on the reproductive tract organs (uterus and cervix), but also on the central and peripheral nerves by regulating expression of various neuronal genes. The peripheral primary afferent neurons innervating the uterine cervix relay mechanical and biochemical sensory information induced by local cervical events and by passage of fetuses, to the spinal cord and supraspinal centers. Consequently, the birth process in mammals is influenced by the combined action of neurons and hormones. Peripheral sensory stimuli, induced physiologically by fetal expulsion or mechanically by vaginocervical stimulation, alter behavior, as well as autonomic and neuroendocrine systems. Recent evidence indicates that primary afferent neurons innervating the cervix, in addition to their sensory effects, likely exert local "efferent" actions on the ripening cervix near term. These efferent effects may involve estrogen-regulated production of such neuropeptides as substance P and calcitonin gene-related peptide in lumbosacral dorsal root ganglia, and their release in the cervix. Collectively, these findings suggest an interrelationship among estrogen, cervix-related sensory neurons, and local cervical events near term.
Mowa C N; Papka R E
The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society
2004
2004-10
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1177/002215540405201001" target="_blank" rel="noreferrer noopener">10.1177/002215540405201001</a>