Immunophenotypic characteristics of inducible NO synthase expression in dentate gyrus of mature rats in modeling depression and its pharmacological correction

AIM: The work aimed to investigate inducible NO synthase (iNOS) expression in dentate gyrus in mature rats when modeling depression, as well as the establish the pharmacological correction possibility of detected changes with Phenibut and compounds under laboratory codes of RSPU-189, RSPU-135. MATERIALS AND METHODS: Depressive-like behavior in animals was modeled by combining stressful stimuli such as loud sound, pulsating bright light, and vibration simultaneous with constant restriction of mobility and fluctuations in temperature of environment for 7 days (daily for 30 minutes). Changes in level of iNOS expression in dentate gyrus were assessed by calculating relative area of immunoreactive material (IRM) and staining intensity in points from 0 to 3. RESULTS: Compared with the control group, rats with experimental depression showed an increase in expression of iNOS-IRM in cytoplasm of neuronal perikarya in granular layer of dentate gyrus, as well as an increase in relative area of iNOS-IRM in neuropil and nerve cells. The use of the compound RSPU-189 (salifen) demonstrated to a greater extent the corrective effect, since in the cytoplasm of neuronal perikarya in granular layer of dentate gyrus of rats, there was a decrease in the expression of iNOS-IRM, as well as a decrease in the relative area of iNOS-IRM in neuropil and nerve cells, which corresponded to values of these parameters in the control group of animals. CONCLUSIONS: An experimental modeling of depression in dentate gyrus of mature rats revealed an increase of iNOS-IRM expression, the decrease of which was noted in its pharmacological correction with the compound RSPU-189 (salifen), which may indicate the predominant neuroprotective effect of this compound on GABAergic neurotransmission mechanisms.