In vitro research of the alteration of neurons in vagal core in medulla oblongata at asphyxic deaths.

Naim Haliti,Hilmi Islami,Bedri Abdullahu,Gani Dragusha,Nevzat Elezi,Ragip Shabani

doi:10.17305/bjbms.2010.2695

Naim Haliti, Hilmi Islami + Show 4 more

Open Access

https://doi.org/10.17305/bjbms.2010.2695

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Abstract

The aim of this study was to research the morphological changes of neurons in the vagus nerve nuclei in medulla oblongata in asphyxia related death cases. Morphological changes that were investigated were mainly in the dorsal motor respiratory center (DMRC), nucleus tractus solitarius (nTS) and nucleus ambigus (nA) in the medulla oblongata. In our research, the autopsy material from asphyxia related death cases was used from various etiologies: monoxide carbon (CO), liquid drowning, strangulation, electricity, clinical-pathological death, firing weapon, explosive weapon, sharp and blunt objects and death cases due to accident. The material selected for research was taken from medulla oblongata and lungs from all lobes. The material from the medulla oblongata and lungs was fixed in a 10% solution of buffered formalin. Special histochemical methods for central nervous system (CNS) were employed like: Cresyl echt violet, toluidin blue, Sevier-Munger modification and Grimelius. For stereometrical analysis of the quantitative density of the neurons the universal testing system Weibel M42 was used. The acquired results show that in sudden asphyxia related death cases, there are alterations in the nuclei of vagal nerve in form of: central chromatolysis, axonal retraction, axonal fragmentation, intranuclear vacuolization, cytoplasmic vacuolization, edema, condensation and dispersion of substance of Nissl, proliferation of oligodendrocytes, astrocytes and microglia. The altered population of vagus nerve neurons does not show an important statistical significance compared to the overall quantity of the neurons in the nuclei of the vagus nerve (p<0.05).

Highlights

Asphyxic lesions cause lethal lesions or nonlethal lesions of health due to respiratory disorders
As a consequence of an accumulation of carbon dioxide (CO ) hypercapnia appears in the organism, and at once final metabolic products are accumulated as well and along with hypercapnia, cause the paralyses of respiratory centres which brings to general strangulation or asphyxia. (, ) Respiratory control is a result of interactive complexes in between neurons and medulla oblongata
Intensity of abovementioned changes is lower in nucleus ambigus (nA) nucleus

Summary

Introduction

Asphyxic lesions cause lethal lesions or nonlethal lesions of health due to respiratory disorders. Three neuronal groups enable normal breathing: dorsal respiratory group (nucleus dorsalis nervus vagus – DMNV, tractus and nucleus solitarius - nTS), ventral respiratory group (Botzinger complex, nucleus retroambigualis and nucleus ambigus), pontin respiratory group (Klliker – Fuse complex and nucleus parabrachialis medialis) Differentiated neurons of these groups are held responsible for the activity of respiratory cycle (Figure ). Coordination of activities of these neurons in a group manner generates the respiratory rhythm.( ) Cell hypoxemic manifestations are well emphasized in hippocampus and in cores of cranial nerves. Changes in neuronal cells caused by hypoxias in animal models are evident following a couple of seconds. Conditions with prolonged hypoxia cause ireversible functional changes and cell damage (cell death), but they can be avoided for a certain time period. Microglial cells, in pathologic conditions, transform into cane cells and participate in the creation of glial noduluses ( , )

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