Bon L.I., Maksimovich N.Ye., Zimatkin S.M.
Morphological changes in the rats’ parietal cortex after subtotal cerebral ischemia and on the background of L-NAME administration
Grodno State Medical University, Grodno, Republic of Belarus
Vestnik VGMU. 2019;18(1):14-20.
Cerebral ischemia is a severe neurodegenerative condition, resulting in deep damage to the central nervous system. Neurons of the neocortex are most sensitive to lack of oxygen. Through the activation of various isoforms of NO-synthase, nitric oxide is involved in the pathogenesis of cerebral ischemia.
Objectives. To study morphological changes in the parietal cortex of rats with subtotal cerebral ischemia on the background of the introduction of a nonselective NO-synthase inhibitor – Nt-nitro-L-Arginine Methyl Ester (L-NAME).
Material and methods. The experiments were performed on 20 female white rats. During the experiments, all the requirements of the Directive of the European Parliament on the protection of animals used for scientific purposes were observed. The control group (group 1) consisted of false-operated rats. Subtotal cerebral ischemia (group 2) was modelled by ligation of both common carotid arteries under thiopental anesthesia. The rats of the second experimental group (group 3) in addition to ligation of both common carotid arteries, were administered a nonselective inhibitor of NO-synthase – L-NAME.
Results. In rats after cerebral ischemia, there was a decrease in the number of normochromic neurons and an increase in the number of pathological forms of neurons. In the rats of the 3rd group, a decrease in the number of hyperchromic unshortened neurons, an increase in the number of hyperchromic wrinkled neurons, compared to group 2 was observed. With morphometry of parietal cortex neurons in rats after cerebral ischemia, a significant decrease in the area of their perikaryons was revealed, they became more elongated and less rounded. In group 3, there was an even more significant decrease in the form factor compared to group 2.
Conclusions. Subtotal cerebral ischemia leads to histological disturbances of neurons in the parietal cortex of rats: a decrease in cell size, a decrease in the number of normochromic neurons and an increase in the number of pathological forms of neurons, and their massive wrinkling. The administration of a non-selective inhibitor of NO-synthase L-NAME aggravated the disorders in question.
Key words: cerebral ischemia, neocortex, N:-nitro-L-Arginine Methyl Ester.
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Information about authors:
Bon L.I. – lecturer of the Chair of Pathological Physiology named after D.A. Maslakov, Grodno State Medical University;
Maksimovich N.Ye. – Doctor of Medical Sciences, professor, head of the Chair of Pathological Physiology named after D.A. Maslakov, Grodno State Medical University;
Zimatkin S.M. – Doctor of Biological Sciences, professor, head of the Chair of Histology, Cytology & Embryology, Grodno State Medical University.