Cardiology Letters 2018, 27(4):185-191

Compensatory effects of nitric oxide and hydrogen sulfide in thoracic aorta in conditions of essential hypertension

Čačáyniová S¹, Berényiová A¹, Cebová M¹, Kristek F1&dagger, Drobná M¹, Ondriaš K², Grman M²

¹ Ústav normálnej a patologickej fyziológie, Centrum experimentálnej medicíny, Slovenská akadémia vied, Bratislava

² Ústav klinického a translačného výskumu, Biomedicínske centrum, Slovenská akadémia vied, Bratislava, Slovenská republika

Several studies have already confirmed the cross-talk between nitric oxide (NO) and hydrogen sulfide (H2S) signaling systems in normotensive rats, but results in spontaneously hypertensive rats (SHRs) are limited. The aim of this study was to describe the vasoactive effects of endogenous NO and exogenous Na2S and their interaction in vasomotor responses of the thoracic aorta (TA) in young (4 weeks old) and adult (16 weeks old) normotensive Wistar rats and SHRs. Although hypertrophy of the heart was observed in young and adult SHRs, the sBP was increased only in adulthood. The contractile responses of the TA were decreased in young as in adult SHRs with the key participation of the endogenous NO/NO-synthase system. NO-dependent component of acetylcholine-induced relaxation was higher in the young SHRs and comparable in the adult SHRs. NOS activity was higher in the young SHRs as well as in the adult SHRs. The acute NO inhibition generally increased the relaxant phase of H2S donor responses; nevertheless, the development of hypertension potentiated this effect. The TA of the SHRs is endowed with a unique inherent predisposition of vasoactive mechanisms, which serve as compensatory processes during the developed stage of hypertension: the NO component and H2S signaling pathways are implicated.

Keywords: nitric oxide; hydrogen sulfide; thoracic aorta; spontaneously hypertensive rats

Published: April 1, 2018  Show citation