Presence of binucleate neurons in the spinal cord of young and senile rats

Abstract

The presence of binucleate cells constitutes a normal feature of some animal tissues but is rare in the normal brain. We assessed different segments of the rat spinal cord in order to determine the frequency and distribution of binucleate neurons in this structure as well as the impact of aging on this neuronal population. Young (4-5 mo.) and senile (32 mo.) female Sprague-Dawley rats were used. Sections from cervical, thoracic and lumbar segments were histochemically stained with cresyl fast violet and the frequency and distribution of binucleate neurons was determined by manual counting. Binucleate neurons were particularly frequent in the C5 and C6 segments. The frequency of binucleate neurons in all of the analysed segments was comparable between young and senile animals. The overall distribution of binucleate neuron frequency in the different laminae assessed was, Lm-III= 19%; Lm-VI= 17%; Lm-VII= 39%; LmVIII= 8%; Lm-IX= 11%; Lm-X= 6%, and was comparable between young and senile rats. We conclude that binucleate neurons occur as a normal feature of the rat spinal cord and that their frequency and distribution does not change with aging.