Contribution of heme oxygenase 2 to blood pressure regulation in response to swimming exercise and detraining in spontaneously hypertensive rats

WOS: 000442483900002 PubMed ID: 30132448 Background: We aimed to determine the effects of exercise followed by detraining on systolic blood pressure (SBP), heme oxygenase 2 (HO-2) expression, and carboxyhemoglobin (COHb) concentration in spontaneously hypertensive rats (SHR) to explain the role of carbon monoxide (CO) in this process. Material/Methods: Animals were randomized into exercised and detrained groups. Corresponding sedentary rats were grouped as Time 1-2. Swimming of 60 min/5 days/week for 10 weeks was applied. Detraining rats discontinued training for an additional 5 weeks. Gene and protein expressions were determined by real-time PCR and immunohistochemistry. Results: Aorta HO-2 histological scores (HSCORE) of hypertensive rats were lower, while SBP was higher. Swimming caused enhancement of HO-2 immunostaining in aorta endothelium and adventitia of SHR. Exercise induced elevation of blood COHb index in SHR. Synchronous BP lowering effect of exercise was observed. HO-2 mRNA expression, HSCORE, and blood COHb index were unaltered during detraining, while SBP was still low in SHR. Conclusions: CO synthesized by HO-2 at least partly plays a role in SBP regulation in the SHR-and BP-lowering effect of exercise. Regular exercise with short-term pauses may be advised to both hypertensives and individuals who are at risk. Pamukkale University Scientific Research Projects Coordination UnitPamukkale University [2012ARS002, 2013SBE002, 2016HZLDP018, 2018KRM002-201] This study is part of a PhD thesis and was supported by Pamukkale University Scientific Research Projects Coordination Unit through project numbers 2012ARS002, 2013SBE002, 2016HZLDP018 and 2018KRM002-201