Naslov
Effects of hyperbaric oxygen therapy on the mechanisms of acrtylcholine-induced vascular relaxation in normal and streptozocin-diabetic rats

Autori
Mihalj, Martina ; Unfirer, Sanela ; Gros, Mario ; Brizić, Ivan ; Budimir, Danijela ; Boban, Mladen, Drenjancevic, Ines

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of abstracts, 9th World Congress for Microcirculation, Paris, France, 2010 / - , 2010

Skup
9th World Congress for Microcirculation

Mjesto i datum
Pariz, Francuska, 26.09.2010. - 28.09.2010

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
hyperbaric oxygen therapy; microcirculation

Sažetak
The aim of this study was to evaluate effects of hyperbaric oxygen therapy (HBOT) on vascular function in healthy and streptozocin-induced diabetic rats (DM) and to elucidate the mechanisms by which HBOT might protect vascular relaxation. Fifty-five male Sprague Dawley rats were randomized into five groups: (A) rats treated with citric acid buffer, (B) healthy controls, (C) DM+HBOT, (D) DM and (E) healthy controls + HBOT. Vascular responses to cumulative concentration of acetylcholine or SNP in PE-precontracted aortic rings were measured with/without presence of indomethacin, L-NAME or clotrimazol. Plasma antioxidative capacity was measured with FRAP assays and the systemic oxidative stress with TBARS assay. The data were analyzed with two-way ANOVA RM and Bonferroni posttest and considered significant if p<0.05. Vascular relaxation to 10-7M of ACh, in absence of a any inhibitor, was significantly improved (p<0, 001) in healthy + HBOT rats ; furthermore the same group showed enhanced response to the same concentration of ACh in presence of indomethacin (p<0, 001) compared to all other groups. In the presence of L-NAME ; ACh-induced relaxation in DM+HBOT rats was partially preserved (p<0, 001) in contrast to all other groups where relaxation was eliminated. The relaxation in response to SNP was preserved in all groups. There was no difference in antioxidative capacity between the groups (p=0, 72), however the oxidative stres was significantly higher in both DM and DM+HBOT groups compared to other groups. Enhanced vascular relaxation in healthy controls treated with HBOT could be a sign of improved endothelial function whose mechanism doesn't seem to be related to prostaglandins. Positive effects of HBOT on DM appears not to be mediated through eNOS but other metabolites. HBOT doesn't induce oxidative stress which would contribute to observed responses. Further investigations with high-specific inhibitors are necessary to elucidate highly specific mechanisms of HBOT's beneficial effects on vasculature.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

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