The effect of zinc complex of N-isopropenylimidazole on the morphological characteristics of gum tissues in experimental endodontic-periodontal lesions in rats Authors

Introduction: Combined inflammatory and destructive processes affecting the dental pulp and tissues of the periodontal complex are among the most problem diseases of the dental system. Current therapy with use of available pharmacological agents does not always allow achieving the expected positive result. In addition, often the lack of information about morphological processes in the tissues of the dental system, in particular the gums, with endodontic-periodontal lesion (EPL) limits the ability of dentists to carry out targeted pharmacotherapy with both traditional and, in particular, new medications. The aim of the study was to evaluate the morphological characteristics of gum tissues in a therapeutic context of N-isopropenylimidazole zinc complex derivative in experimental endodontic-periodontal lesion in rats. Materials and Methods: A simulation of EPL in rats was performed in two ways: simultaneous induction of acute periodontitis and parodontitis by pulp extraction and natural infection of the pulp cavity, as well as by ligation of the necks of lower incisors. The research protocols included 5 groups of animals: 1st – intact group (control-1); 2nd – animals with simulated EPL (control-2); 3rd – animals with simulated EPL and treated with Metrogyl Denta® gel (M-D); 4th – animals with simulated EPL and treated with N–isopropenylimidazole zinc complex derivative gel under the laboratory code Pilim-1; and 5th – animals with simulated EPL and treated with the combination of M-D + Pilim-1. The gum of the lower incisors was taken for morphological studies. Slides were stained with hematoxylin and eosin. Computer morphometry was performed using the ImageJ software. Results and Discussion: The substances M-D, Pilim-1 and, especially, the combination of M-D+Pilim-1 (against the background of chlorhexidine bigluconate used as oral rinse) for 14 days in rats with simulated EPL cause a significant improvement of the morphological structure of the gum with minimal residual dystrophy and sclerosis. The combination M-D + Pilim-1 led to a 1.3-time increase in epithelial thickness, and a 1.5-time decrease in acanthosis depth in comparison with M-D, while the number of capillaries and their diameter had no significant differences. Compared with Pilim-1, the epithelial thickness increased 1.5 times, and the acanthosis depth and the number of capillaries decreased 1.6 and 1.4 times, respectively, whereas the diameter of the capillaries did not change significantly. The pronounced protective effect of the combination M-D + Pilim-1 on the morphological structure of the gingival mucosa of rats with simulated EPL may be associated with antimicrobial, anti-inflammatory, regenerating, angioprotective and antioxidant properties of both M-D and Pilim-1 separately, and, possibly to a greater extent, of the combination M-D + Pilim-1. Conclusion: The substances M-D, Pilim-1 and, especially, the combination M-D + Pilim-1 (against the background of chlorhexidine bigluconate used as oral rinse) for 14 days in rats with simulated EPL have a protective effect on the epithelial structure and the connective tissue of the proper mucous plate, manifested in active normalization of pathological changes and significant restoration of their organotypic structure

Effects of Dimephosphone on skin survival in conditions of reduced blood circulation

Introduction: The search for and creation of drugs with dermatoprotective and metabotropic activity is one of the priorities of modern diabetology. Synthetic organophosphorus compounds with no anticholinesterase activity, to which Dimephosphone belongs to, deserve great attention in this respect. Materials and Methods: Experiments included 355 white non-linear male mice (18-34 g) and 799 male rats (150–305 g). The dermatoprotective activity (DPA) of Dimephosphone regarding the survival of a skin graft was studied against the background of normoglycemia, as well as against the background of experimental diabetes complicated by hypercholesterolemia. The study of microhemodynamics in the skin was performed using laser Doppler flowmetry. The effects on metabolic processes and the antioxidant system were studied by determining the levels of glucose, urea, creatinine, total bilirubin, total cholesterol, triglycerides, total protein, albumin, globulin, catalase, malondialdehyde, superoxide dismutase, glutathione reductase, glutathione and glutathione peroxidase. Results: Dimephosphone has a pronounced DPA in conditions of reduced blood circulation against the background of normoglycemia and experimental (alloxan) diabetes complicated by exogenous hypercholesterolemia. By DPA, in most cases against the background of normoglycemia Dimephosphone exceeds Actovegine, is comparable to or inferior to Trental and Mexidol, and is more significant in terms of the therapeutic width than all the drugs taken for comparison. Discussion: According to the obtained data , DPA of Dimephosphone may be due to its ability to exhibit significant vasodilating, antihypoxic, antioxidant, antiaggregant, membrane-stabilizing, anti-acidotic, antimicrobial and other properties and also to exert a normalizing effect on carbohydrate, protein, lipid and energy metabolism Conclusion: Dimephosphone can be recommended for further preclinical and clinical studies in the form of various dosage forms, as well as in a combination therapy for metabolic disorders

The effectiveness of Soderm® – forte gel and a new injectable dosage form of Rexod® in the complex treatment of experimental periodontitis in rats

Introduction: Insufficient effectiveness of traditional drug therapy in a treatment of patients with chronic generalized periodontitis, as well as high social significance of this problem, determines the need to search for new drugs and their compositions aimed at solving it. Aim of the study: To increase the efficacy of complex treatment of periodontitis with the administration of Soderm®-Forte gel and a new injectable form of Rexod®. Materials and methods: Experiments were performed in 50 male Wistar rats. Experimental periodontitis (EP) was simulated by ligation of the necks of lower incisors. We studied the animals with intact periodontium, untreated EP, and when traditional drug therapy (TDT), as well as the combinations of TDT with Soderm®-Forte gel and additionally with the new injectable dosage form (NIF) of Rexod® were administered. The general condition, behavior, nutrition and body weight of the animals were evaluated. The Schiller-Pisarev test and the Muhlemann-Cowell bleeding index were used, and the amount of crevicular fluid (CF) was measured. The contamination of the marginal gum with microorganisms was determined. Results and discussion: The TDT in EP has a moderate therapeutic effect, which does not lead to a sufficiently high pharmacotherapeutic effect, whereas the combinations of TDT with Soderm®-Forte and, to a greater extent, TDT with Soderm®-Forte and NIF of Rexod® have high therapeutic efficacy, which is statistically confirmed by a sharp decrease in the amount of CF, the Schiller-Pisarev test and the Muhlemann-Cowell bleeding index, as well as absolute suppression of pathogenic microorganisms. Conclusion: The combinations of TDT with Soderm®-Forte gel and NIF of Rexod® in EP in rats can significantly increase the effectiveness of the treatment. The data obtained indicate the expediency of the administration of Soderm®-Forte gel, as well as its combination with NIF of Rexod® in dental practice in the complex therapy of patients with periodontitis

The effect of the composition of Soderm®-Forte gel and the new injectable form of Rexod® on pathology findings in gingival tissue in experimental periodontitis in rats

Introduction: Periodontitis is the most important problem of modern dentistry. The development of new medicines and treatment regimens for patients with periodontal complex lesions is a strategic direction of modern pharmacology and dentistry. In this view, pride of place goes to morphological research, which allows not only to study the effect of drugs on pathomorphological changes in periodontal tissues, but also to estimate their therapeutic effectiveness. Aim of the study: to determine the nature of the effect of the composition of Soderm®-Forte gel and the new injectable form of Rexod® on the pathology findings in gingival tissue of rats with experimental periodontitis. Materials and methods: Experimental periodontitis (EP) was induced in rats by ligature method. The study was performed according to the following algorithm: animals with intact periodontium; animals with untreated EP; animals with EP treated with traditional drug therapy (TDT); animals with EP treated with combinations of TDT with Soderm®-Forte gel and TDT with Soderm®-Forte gel and the new injectable form (NIF) of Rexod®. For pathomorphological examination, biopsy specimen was taken from the gingival margin of the lower incisors. The ImageJ software was used for computer morphometry. Results and discussion: Examination of the gum samples revealed moderate therapeutic effects of the TDT. The combinations of TDT with Soderm®-Forte gel and, to a greater extent, TDT with Soderm®-Forte gel and the NIF of Rexod® showed high pharmacotherapeutic efficacy, manifested in rapid regeneration of the gingival tissues. Conclusion: The combination of TDT, Soderm®-Forte gel and the NIF of Rexod® shows the most beneficial effect on the pathological processes in the gum. The pharmacotherapeutic effect of the studied combination promotes the earliest regeneration of damaged gum tissues and reduces the risk of persistent pathology changes in them

Mafusol and its combination with REXOD as correctors of reduced blood circulation in the skin associated with normoglycemia or diabetes mellitus complicated by exogenous hypercholesterolemia

Introduction: The search for and development of new highly active medications and their combinations of the appropriate direction of action remains an urgent problem due to the complications of diabetes mellitus, especially burdened with atherosclerosis, including skin and vascular lesions. Materials and methods: The acute toxicity, histoprotective and dermatoprotective effects of mafusol, rexod, alprostadil and their combinations were studied in male rats with normoglycemia and alloxan diabetes complicated by exogenous hypercholesterolemia. Results: The combination of mafusol with rexod is less toxic than mafusol. In arteriovenous insufficiency of the tail, ischemia of the skin fold and skin flap, mafusol (6.25, 12.5 and 25.0 mg/kg in terms of fumarate), rexod (0.01 and 0.02 mg/kg) and especially their combination (6.25 and 0.01 mg/kg) have significant histoprotective, dermatoprotective, hypoglycemic and lipid-lowering effects, both in normoglycemia and alloxan diabetes complicated by exogenous hypercholesterolemia. Alprostadil (10 mg/kg) and especially its combination with mafusol (6.25 mg/kg) have a dermatoprotective effect. Discussion: Rexod reduces the acute toxicity of mafusol. The dermatoprotective effect of mafusol, rexod and, to a greater extent, their combination may be associated with increased microhemocirculation, antihypoxic properties and activation of energy processes in the skin, normalization of carbohydrate and lipid metabolism in alloxan diabetes, complicated by exogenous hypercholesterolemia, increased reserve capacity of the antioxidant system, and possibly with the ability of mafusol and rexod to reduce blood viscosity and improve rheological properties of the blood. The combination of mafusol with alprostadil increases the dermatoprotective activity of the latter. Conclusion: Combinations of mafusol with rexod and alprostadil can be recommended for clinical study as dermatoprotective agents for treating traumatic injuries and diabetes mellitus complicated by atherosclerosis

Role of indole derivative SS-68 in increasing the frequency range of cardiac rhythm control (reflex stimulation of the sinoatrial node)

Introduction: Cardiac pacing is indicated for sick sinus syndrome. It is performed with a pacemaker via electrodes implanted in the heart. This technique has several disadvantages. The search for alternative methods of cardiac pacing is underway. One of them is control of heart rhythm through stimulation of the tragus. Objective: To perform the reflex stimulation of the sinoatrial node and to study the influence of the SS-68 substance on it. Materials and methods: Two electrodes were fixed in the reflexogenic zone of rabbits’ auricles, volleys of electrical impulses from an electrical stimulator were applied to the electrodes, and the synchronization range of volley frequency and cardiac contractions was recorded. This range was re-recorded again after injecting the SS-68 substance (2-phenyl-1-(3-pyrrolidine-1-cyclopropyl)-1H-indole hydrochloride) intravenously at a dose of 50 µg/kg. In other experiments on frogs in a high-frequency electromagnetic field, the process of excitation of the area of the medulla oblongata associated with the heart rhythm was visualized. After the application of SS-68 (50 μM) to the surface of this zone, the process of its excitation was recorded. Results and discussion: Stimulation of the auricular reflexogenic zone of rabbits produced a synchronization of volley frequency and heart rate in the range from 173.5 ± 2.0 to 214.0 ± 1.8 per minute. SS-68 extended this range from 168.2 ± 1.9 to 219.4 ± 1.5 per minute. In the frog’s medulla oblongata, an area synchronous to the heart rhythm glowed in the high-frequency electromagnetic field. SS-68 increased the area of glow by 131.0%. Conclusion: The substance SS-68 increases the frequency range of heart rhythm control by activating reflex stimulation of the sinoatrial node. The main point of application of SS-68 is the medulla oblongata. Glow in the high-frequency electromagnetic field reflects the process of neuron excitation. The increase in the glow zone under the influence of SS-68 indicates synchronously excited neurons, which leads to the assimilation of the central heart rhythm generation by the sinoatrial node

The influence of the vagus nerve and indole derivative SS-68 on excitation processes in the SA node

Introduction: Atrial fibrillation (AF) is the most common form of cardiac arrhythmias. Studying the pathogenesis of this pathological process will make it possible to look for new methods of treating AF and to predict its occurrence in a more targeted way. The aim of the study was to identify the components of the takeover process of central rhythmogenesis by the SA node in the conditions of atrial fibrillation when stimulating the vagus nerve and using substance SS-68. Materials and Methods: The experiments were conducted on 30 frogs and 90 cats. In frogs, the activity of the regions of the medulla oblongata synchronous with the heart rhythm was determined in a high-frequency electromagnetic field. In cats, proximal and distal foci of luminescence in the vagus nerve (VN) and pools of pacemaker cells (PCs) in the sinoatrial node were visualized under topical and general anesthesia, using a KELSY scanner with a microscope video capture unit while stimulating VN and using SS-68. Results and Discussion: The stimulation of VN with volleys of electrical impulses and the introduction of SS-68 increase the foci of luminescence in the nerve and unite the PC pools. This way, under general anesthesia in comparison with topical anesthesia, the area of the proximal focus of VN luminescence decreased by 83.8%, and the distal focus – by 44.9%. Against the background of general anesthesia, the area of the proximal focus of luminescence when stimulating VN with volleys of electrical impulses was by 76.0% larger than before stimulation, and the distal focus – by 72.5%. After the administration of SS-68, there was an increase in the foci of luminescence: under general anesthesia, when compared with topical anesthesia, the area of the proximal foci of luminescence decreased by 86.8%, and the distal one – by 67.1%. Under general anesthesia, the area of the proximal focus of luminescence under conditions of stimulating VN with volleys of electrical impulses was by 82.2% larger than before stimulation and the distal one – by 78.2%. When signals from the brain arrive simultaneously through VN at the PC pools, they are absorbed by the PC pools; the focus of early depolarization becomes wide, which prevents the development of AF. The increased synchronizing influence of VN may be one of the methods for treating autonomic AF, and if its influence decreases, it can be a prognostic factor for the occurrence of recurrent AF. Conclusion: The tonic effect of VN on the heart rhythm through electrical stimulation of the former and the use of SS-68 is manifested in a decreased heart rate: the difference between the initial heart rhythm and the minimal synchronization range boundary. A decrease in the heart rate under the influence of VN prevents paroxysms of AF, but does not completely eliminate the influence of ectopic foci on it