The present study was undertaken 1) to examine the neuronal mechanisms responsible for the inhibition of spinal cord motoneurons that occurs in alpha-chloralose-anesthetized cats following the microinjection of carbachol into the nucleus pontis oralis (NPO), and 2) to determine whether the inhibitory mechanisms are the same as those that are responsible for the postsynaptic inhibition of motone...

Since its first description in 1874 by Charcot, the hallmark feature of ALS is the progressive degeneration of upper and lower motoneurons (Charcot, 1874). In the spinal cord, motoneuron degeneration starts long before symptom onset and advances in a size-related fashion, in which large-size alpha-motoneurons degenerate first followed by small-size alpha-motoneurons (Pun et al., 2006; Hegedus e...

The purpose of this study was to determine structural changes which trigger the onset and progression of amyotrophic lateral sclerosis in rats expressing a human SOD1 transgene with mutation G93A. Lumbar spinal cord of affected rats in early and late presymptomatic (PM, 60 and 93 days of age) and symptomatic (S, 120 days of age) stage of the disease were analyzed ultrastructurally. At 60 days t...

background and aims: neurons are injured under physical, chemical and pathological conditions. the effect of peripheral nervous system injuries may return as retrograde to the cell body of neurons in central nervous system resulting in brain and spinal cord degeneration. because of high content of camphor and borneol, achillea biebersteinii from asteracea family may be effective in prevention t...

The accumulation of reactive microglia in the degenerating areas of amyotrophic lateral sclerosis (ALS) tissue is a key cellular event creating a chronic inflammatory environment that results in motoneuron death. We have developed a new culture system that consists in rat spinal cord embryonic explants in which motoneurons migrate outside the explant, growing as a monolayer in the presence of g...

Although it is known that noradrenaline (NA) powerfully controls spinal motor networks, few data are available regarding the noradrenergic (NAergic) modulation of intrinsic and synaptic properties of neurons in motor networks. Our work explores the cellular basis of NAergic modulation in the rat motor spinal cord. We first show that lumbar motoneurons express the three classes of adrenergic rec...

Ciliary neurotrophic factor (CNTF) has potent survival-promoting effects on motoneurons in vitro and in vivo. We examined knockout mice with null mutations of the gene for either CNTF itself or the alpha-subunit of the CNTF receptor (CNTFRalpha) to assess whether CNTF and/or its receptors are involved in the development of a sexually dimorphic neuromuscular system. Male rodents have many more m...

Background and Objective: Sciatic nerve transection is characterized by a rapid wave of motoneuron death associated with progressive synaptic lesions. The purpose of this study was to evaluate the long term synaptic changes. Materials and Methods: This basic study was carried out on paraffin- or resin-em...

We generated retinoid-deficient adult rats by the removal of retinoids from their diet. We show that their motoneurons undergo neurodegeneration and that there is an accumulation of neurofilaments and an increase in astrocytosis, which is associated with motoneuron disease. These effects are mediated through the retinoic acid receptor alpha. The same receptor deficit is found in motoneurons fro...