time course of axotomy-induced changes in synaptophysin pattern and synaptic reaction of spinal motoneurons in adult rat

Authors

alireza azizzadeh delshad

taki tiraihi

abstract

background and objective: evaluation of degenerative changes of motoneurons and their related synapses can be useful in understanding the mechanisms of neurodegenerative diseases and their potential treatment. the present electron microscopic and immunohistochemical study investigates the axotomy-induced changes of adult spinal motoneurons up to 3 months following sciatic nerve transection. materials and methods: following unilateral mid-thigh sciatic transection in adult rats, the synaptophysin expression and ultrastructure of synapses in ventral horn of related spinal cord segments were studied 1 day, 1 week, 1 month, and 3 months postoperatively. in all groups the unaxotomized side of spinal cord was considered as control. the pattern of synaptophysin immunolabeling was classified into intact, partial, diffused, and negative types. results: in 1 week and 1 month groups, the intact pattern decreased and the other 3 patterns increased, whereas 3 months postoperatively the patterns changed vice versa, i.e. intact pattern increased and the other 3 decreased. electron microscopic studies indicated consistent ultrastructural changes such as synaptic vesicle displacement, synaptic membrane irregularity and synaptic stripping, which were most prominent after 1 month and declined in 3 month group. conclusion: the present data indicate that following axon injury in adult motoneurons, synapses undergo obvious changes in ultrastructure and synaptophysin distribution, which increase up to 1 month postoperatively, and if the cell survives the insult the changes will attenuate and return to normal conditions thereafter.

Upgrade to premium to download articles

Sign up to access the full text

Already have an account?login

similar resources

Time Course of Axotomy-induced Changes in Synaptophysin Pattern and Synaptic Reaction of Spinal Motoneurons in Adult Rat

Background and Objective: Evaluation of degenerative changes of motoneurons and their related synapses can be useful in understanding the mechanisms of neurodegenerative diseases and their potential treatment. The present electron microscopic and immunohistochemical study investigates the axotomy-induced...

full text

Time Course of Axotomy-induced Changes in Synaptophysin Pattern and Synaptic Reaction of Spinal Motoneurons in Adult Rat

Background and Objective: Evaluation of degenerative changes of motoneurons and their related synapses can be useful in understanding the mechanisms of neurodegenerative diseases and their potential treatment. The present electron microscopic and immunohistochemical study investigates the axotomy-induced changes of adult spinal motoneurons up to 3 months following sciatic nerve transection. Mat...

full text

Time course of adult castration-induced changes in soma size of motoneurons in the rat spinal nucleus of the bulbocavernosus.

The spinal nucleus of the bulbocavernosus (SNB) innervates striated muscles, the bulbocavernosus and levator ani (BC/LA), which control penile reflexes. Castration results in shrinkage in the size of SNB somata and dendrites, as well as BC/LA muscle mass. However, there is no information about how quickly these regressive changes occur compared to the rapid effects of castration upon penile ref...

full text

Calcitonin gene-related peptide in rat spinal cord motoneurons: subcellular distribution and changes induced by axotomy.

Using light and electron microscopy, a study has been made of the changes of calcitonin gene-related peptide-like immunoreactivity in rat lumbar spinal cord motoneurons during cell body response to sciatic nerve injury. At light microscopy level, calcitonin gene-related peptide-like immunoreactivity was evaluated using an indirect immunofluorescence technique combined with Fast Blue retrograde ...

full text

Delayed Synaptic Changes in Axotomized Spinal Motoneurons of Newborn Rats Associated with Progressive Neuronal Loss: Immunohistochemical, Ultrastructural, and Quantitative Study

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...

full text

Time course changes of oxidative stress and inflammation in hyperoxia-induced acute lung injury in rats

Objective(s):Therapies with high levels of oxygen are commonly used in the management of critical care. However, prolonged exposure to hyperoxia can cause acute lung injury. Although oxidative stress and inflammation are purported to play an important role in the pathogenesis of acute lung injury, the exact mechanisms are still less known in the hyperoxic acute lung injury (HALI).   Materials ...

full text

My Resources

Save resource for easier access later


Journal title:
iranian journal of pathology

Publisher: iranian society of pathology

ISSN 1735-5303

volume 2

issue 3 2007

Hosted on Doprax cloud platform doprax.com

copyright © 2015-2023