INVESTIGATION OF METABOLIC DISORDERS IN VARIOUS ORGANS IN WATER-IMMERSION RESTRAINT STRESS IN RATS AND ITS CORRECTION WITH PHARMACEUTICALS
Authors: Khavrona O.P. , Biletska L.P. , Myhal L.R. 
Published: August 2024

The aim of the study. To investigate the impact of L-arginine and diclofenac sodium on changes in the prooxidant-antioxidant balance in liver, spleen and lungs in water-immersion restraint stress in rats.
Materials and methods. The study was conducted on 50 male rats weighing 180-240 g in accordance with the international bioethical principles. Water-immersion restraint stress (WIRS) was modeled according to the method of Takagi et al. Experimental animals were studied in five groups (n = 10 per group) as follows: (1) intact animals; (2) those in which WIRS was simulated; (3) animals receiving diclofenac sodium (40 mg/kg) per os 30 minutes before WIRS; (4) animals receiving L-arginine (10 mg/kg) per os 30 minutes before WIRS. For sample collection, the rats were deeply anesthetized (thiopental sodium, 40 mg/kg). The liver, spleen and lungs were isolated and homogenized. The state of antioxidant defense system was assessed by the activity of superoxide dismutase (SOD) and catalase (CAT). To evaluate the activity of prooxidative processes, the levels of thiobarbituric acid reactive substances (TBARS), oxidative protein modification (OPM) and middle mass molecules (MMM) were investigated. The statistical analysis was performed according to Student’s criterion, using Microsoft Excel 8.0 software. Differences were considered statistically significant at p<0,05.
Result. The development of WIRS led to the increase in the prooxidant processes intensity in liver: TBARS by 41%, OPM by 76%, MMM by 160%; in lungs: TBARS by 43%, OPM by 71%, MMM by 99%; in spleen: TBARS by 110%, OPM by 87%, MMM by 205%. When corrected with diclofenac sodium, a decrease in prooxidant processes was observed in the liver: TBARS by 27%, OPM by 48%, MMM by 34%; in the lungs: TBARS by 23%, OPM by 40%, MMM by 19%; in the spleen: TBARS by 28%, insignificant decrease in OPM, MMM by 37%. The activity of these processes decreased in all organs also when the condition was corrected with L-arginine, although less noticeably: in the liver: TBARS by 23%, OPM by 31%, MMM by 11%; in the lungs: TBARS by 14%, OPM by 19%, MMM by 11%; in the spleen: TBARS by 32%, no statistically significant decrease in OPM, MMM by 27%. The activity of antioxidant enzymes under the conditions of WIRS development abruptly decreased in the liver: SOD by 42% and CAT by 30%; in the lungs: SOD and CAT by 30%; in the spleen: SOD by 56%, CAT by 40%. The administration of diclofenac sodium led to an increase in the activity of these enzymes in the liver: SOD by 49%, CAT by 17%; in the spleen: SOD by 51%, CAT by 17%; no significant change in CAT; in the lungs: SOD by 17% and no significant change in CAT. The administration of L-arginine had less effect on the normalization of antioxidant enzyme activity. The activity of SOD increased by 20%, CAT – by 12% in the liver; in the lungs SOD and CAT did not increase reliably, only a tendency to increase was observed; in the spleen, the activity of SOD increased by 29%, and CAT by 15%. The combined effect of both drugs showed the best results: normalization of prooxidant processes was observed, only the level of endogenous intoxication remained slightly elevated in all studied organs. The activity of antioxidant enzymes coincided with the level of control indicators. The obtained result indicates the expediency of the combined use of the studied pharmaceuticals.
Conclusions

It was found that the greatest changes in the pro- and antioxidant balance under the influence of stress factors were observed in the spleen, slightly less distinct in the liver, and minor in the lungs of the studied animals.
It was shown that diclofenac sodium at a dose of 40 mg/kg significantly reduced the level of prooxidant markers, manifested a normalizing effect on the activity of antioxidants in all studied organs of rats. The drug reliably increased the activity of SOD and contributed to the stabilization of catalase activity.
The administration of L-arginine at a dose of 10 mg/kg under the same conditions was marked by a decrease in prooxidant processes, a significant increase in SOD activity in the liver and spleen, and a tendency to increase catalase and superoxide dismutase activity in the lungs of rats.
The study revealed that the combination of the pharmaceuticals had the most significant effect on the state of pro- and antioxidant system, since the activity of SOD and catalase increased to the control group values, which was accompanied by a serious decrease in the level of prooxidant indicators to the control values.