First histopathological bridging of the distance between Onufʼs nucleus and substantia nigra after olfactory bulbectomy—new ideas about the urinary dysfunction in cerebral neurodegenerative disease: an experimental study

Objectives: Olfactory bulbectomy (OBX) in experimental studies induces neurochemical, neurodegenerative changes in various parts of the body. But no information is available about how OBX affects the spinal cord in rats. Our study aims to investigate this question. Methods: Twenty-eight male rats were used. The rats were divided into three groups: six as the control, six as the SHAM, and 16 as the study group in which OBX was performed. The animals were followed for 10 weeks. After decapitation of the animals, olfactory bulb (OB) volumes, the olfactory glomerulus (OG), and the neuron density of the ON (Onuf nucleus) per cubic centimeter at the L4-S4 level were examined histopathologically and analyzed stereologically. Results: The mean OB volume, remaining normal OG density, and degenerated neuron density (DND) of the ON was measured as 4.32 ± 0.21/mm3, 1842 ± 114/mm3, and 4 ± 1 /mm3 in the control (group I); 3.3 ± 0.14/mm3, 1321 ± 114/mm3, and 43 ± 8/mm3 in the SHAM (group II); and 1.672 ± 0.12/mm3, 852 ± 93/mm3, and 154 ± 11/mm3 in the study group (group III). There was a statistically significant difference between the SHAM and the study group (P <.05). Conclusions: In this study, histopathological bridging between ON-related lower urinary tract symptoms (LUTS) and OBX was shown the first time. According to the findings, LUTS may be reversed by the protection of the affected spinal cord through the correction of olfaction impairment in neurodegenerative disease. © 2020 John Wiley & Sons Australia, Ltd