shoulder movements are a complex motor act, controlled by many muscles attached to thescapula and the vertebral column. these muscles are innervating by motoneurons (mns) located in theventral horn of the spinal cord. motoneurons of the ventral horn are arranged such that several groups ofmns can be distinguished in a transverse section through the spinal cord. the anatomical or functionalimpli...

The proper assembly of neural circuits during development requires the precise control of axon outgrowth, guidance, and arborization. Although the protocadherin family of cell surface receptors is widely hypothesized to participate in neural circuit assembly, their specific roles in neuronal development remain largely unknown. Here we demonstrate that zebrafish pcdh18b is involved in regulating...

Diversity in the expression of K(+) channels among neurons allows a wide range of excitability, growth, and functional regulation. Ether-à-go-go (EAG), a voltage-gated K(+) channel, was first characterized in Drosophila mutants by spontaneous firing in nerve terminals and enhanced neurotransmitter release. Although diverse functions have been ascribed to this protein, its role within neurons re...

objective(s): umbilical cord blood-derived mesenchymal stromal cells (ucb-mscs) are ideally suited for use in various cell-based therapies. we investigated a novel induction protocol (nip) to improve the neuronal differentiation of human ucb-mscs under appropriate conditions. materials and methods: this experimental study was performed in iranian blood transfusion organization (ibto), tehran, i...

The development of respiratory motoneurons provides unique data that may be generalized to other mammalian motoneuron populations. Like other motoneurons, respiratory motoneurons undergo developmental changes in the shape of the action potential and their repetitive firing. The unique observations concern the postnatal change in the recruitment pattern of cat phrenic motoneurons that is correla...

The dopamine system plays an integral role in motor physiology. Dopamine controls movement by modulation of higher-order motor centers (e.g., basal ganglia) but may also regulate movement by directly controlling motoneuron function. Even though dopamine cells synapse onto motoneurons, which themselves express dopamine receptors, it is unknown whether dopamine modulates skeletal muscle activity....

AMPA receptor-mediated excitotoxicity is proposed to play a major pathogenic role in the selective motoneuron death of amyotrophic lateral sclerosis. Motoneurons have been shown in various models to be more susceptible to AMPA receptor-mediated injury than other spinal neurons. It has been hypothesized that this selective vulnerability of motoneurons is caused by the expression of highly Ca(2+)...

Mechanisms inducing neuronal death at defined times during embryogenesis remain enigmatic. We show in explants that a developmental switch occurs between embryonic day 12 (E12) and E13 in rats that is 72– 48 hr before programmed cell death. Half the motoneurons isolated from peripheral tissues at E12 escape programmed cell death, whereas 90% of motoneurons isolated at E13 enter a death program....

Motoneurons from E14 rat embryos have been retrogradely labeled with the carbocyanine derivative dil and purified 12-fold by centrifugation on a density gradient made of Nycodenz, as assessed by the increase in CAT activity per cell and in the percentage of dil-labeled cells. A 20- to 36-fold purification was achieved by the microdissection of the labeled lumbar motor columns followed by densit...

Amyotrophic lateral sclerosis (ALS) is a rapidly evolving and fatal adult-onset neurological disease characterized by progressive degeneration of motoneurons. Our previous study showed that glycinergic innervation of spinal motoneurons is deficient in an ALS mouse model expressing a mutant form of human superoxide dismutase-1 with a Gly93→Ala substitution (G93A-SOD1). In this study, we have exa...