Papaverine-induced and endothelium-dependent relaxation in the isolated rat aortic strip.

In the present study, we aimed to obtain further evidence in favour of the hypothesis that nitric oxide (NO) is a major mediator of endothelium-dependent vasorelaxation and to clarify whether NO plays a role in papaverine-induced vasorelaxation. The relaxant effects of acetylcholine (Ach), acidified NaNO2 or papaverine were investigated on isolated helical strips of the rat thoracic aorta precontracted with phenylephrine in an organ bath containing Krebs solution aerated with 95% O2 and 5% CO2. The relaxation was quantified as % peak reduction of phenylephrine contracture. Saponin abolished the relaxant effects of Ach completely whereas it had no effect on the responses to acidified NaNO2 or papaverine. NG-nitro-L-arginine (L-NOARG) reduced the effects of Ach significantly, but it was ineffective on the relaxation induced by acidified NaNO2. The inhibitory action of L-NOARG was partly restored by L-arginine, but not by D-arginine. Hemoglobin, hydroxocobalamin and hydroquinone exhibited significant inhibition on the relaxation evoked by Ach and acidified NaNO2. L-NOARG, hydroxocobalamin and hydroquinone caused only limited but significant decrease in the relaxation due to papaverine. This phenomenon was also observed by increasing phenylephrine concentration leading to an enhancement in the contraction. Our findings strongly support the view that Ach-induced relaxation of rat aorta strips is mediated by free NO released from the endothelium and the results suggest that NO may indirectly contribute to papaverine-induced relaxation.</p

Pulsed magnetic field action on antioxidant system in lambda-carrageenan induced acute paw edema

WOS: 000414861000004Purpose: lambda-Carrageenan-induced (lambda-Carr) paw edema is a commonly used test for determining the acute phase of inflammation. In the present study, our aim was to investigate whether efficacy of pulsed magnetic field (PMF) on antioxidant enzymes levels is lambda-Carr-induced rat paw edema. Material and Methods: The rats were whole-body exposed to PMF (1.5 mT intensity and 1, 10, 20, 40 Hz consecutive frequencies between Helmholtz coils) at the same hour in an hour in a day throughout 4 days at 3 hour later from injection of lambda-Carr. Paw edema was determined at the end of fourth day by killing the rats, removed the paws at the ankle joint and paw mass (g) and paw thickness (mm) were was determined the right and left paw of rats. Then, the paw tissues were collected for the measurement of lipid peroxidation (Malondialdehyde; MDA) and antioxidant enzymatic activity levels (Catalase; CAT). Results: Carrageenan-induced right paw masses and paw thicknesses increased in compare to left paw of rats. While CAT levels were significantly decreased, MDA levels were increased in the carrageenan-induced rat right hind paw compare to control rat left paw. After exposed PMF to lambda-Carr- induced right paw, while the CAT enzyme level decreased, the MDA enzyme level increased and there was no significant change in the weight and thickness of the right paw compare to unexposed groups. Conclusion: PMF increased edema in the rat paw and negatively affected antioxidant enzyme levels

The effects of pulsed magnetic field on the key elements responsible for synthesis and destruction of elastin-collagen in diabetic lung tissue

Changes in the expression levels of genes responsible for synthesis-destruction of elastin-collagen and the occurrence of lung diseases are in correlation. Although, diabetes-related complications are important health problems, the mechanism by which diabetes exerts this effect is unclear. On the other hand, although the effect of pulsed magnetic field (PMF) in lung diseases has been shown, its mechanism of action is unknown. The study aimed to determine the effects of PMF on the key regulator elements of the synthesis-destruction of elastin-collagen at the transcriptional level. Rats were divided into groups as control, control + PMF 10Hz, diabetes, diabetes + PMF 10Hz. PMF groups were exposed to 10 Hz PMF for four weeks. In diabetic conditions, ELN, ELANE, and COL1A1 genes were dysregulated at the transcriptional level as their levels were 14.23±2.56; 7.62±1.37 and 0.24±0.04, respectively. Dysregulated ELN gene expressions were decreased to 6.17±1.97 by PMF application. There were no meaningful changes in gene expressions in control + PMF 10 Hz groups. The present study shows that ELN, ELANE, and COL1A1 may play a key role at the transcriptional level in the mechanism of diabetic-lung diseases. In addition, it may be said that &quot;PMF shows its effect by re-regulating the expression level of ELN gene in diabetic lung tissues&quot;. In future studies, ELN gene-targeted PMF application methods may be developed. Moreover, PMF application might not affect the genes that are responsible for elastin-collagen synthesis-destruction in healthy lungs when the PMF is applied on different tissues for the treatment of various diseases. [Med-Science 2022; 11(2.000): 586-92