TY - JOUR
AU1 - Hahnova, Klara
AU2 - Brabcova, Iveta
AU3 - Neckar, Jan
AU4 - Weissova, Romana
AU5 - Svatonova, Anna
AU6 - Novakova, Olga
AU7 - Zurmanova, Jitka
AU8 - Kalous, Martin
AU9 - Silhavy, Jan
AU1 - Pravenec, Michal
AU1 - Kolar, Frantisek
AU1 - Novotny, Jiri
AB - The β-adrenergic signaling pathways and antioxidant defence mechanisms play important roles in maintaining proper heart function. Here, we examined the effect of chronic normobaric hypoxia (CNH, 10% O2, 3 weeks) on myocardial β-adrenergic signaling and selected components of the antioxidant system in spontaneously hypertensive rats (SHR) and in a conplastic SHR-mtBN strain characterized by the selective replacement of the mitochondrial genome of SHR with that of the more ischemia–resistant Brown Norway strain. Our investigations revealed some intriguing differences between the two strains at the level of β-adrenergic receptors (β-ARs), activity of adenylyl cyclase (AC) and monoamine oxidase A (MAO-A), as well as distinct changes after CNH exposure. The β2-AR/β1-AR ratio was significantly higher in SHR-mtBN than in SHR, apparently due to increased expression of β2-ARs. Adaptation to hypoxia elevated β2-ARs in SHR and decreased the total number of β-ARs in SHR-mtBN. In parallel, the ability of isoprenaline to stimulate AC activity was found to be higher in SHR-mtBN than that in SHR. Interestingly, the activity of MAO-A was notably lower in SHR-mtBN than in SHR, and it was markedly elevated in both strains after exposure to hypoxia. In addition to that, CNH markedly enhanced the expression of catalase and aldehyde dehydrogenase-2 in both strains, and decreased the expression of Cu/Zn superoxide dismutase in SHR. Adaptation to CNH intensified oxidative stress to a similar extent in both strains and elevated the IL-10/TNF-α ratio in SHR-mtBN only. These data indicate that alterations in the mitochondrial genome can result in peculiar changes in myocardial β-adrenergic signaling, MAO-A activity and antioxidant defence and may, thus, affect the adaptive responses to hypoxia.
TI - β-Adrenergic signaling, monoamine oxidase A and antioxidant defence in the myocardium of SHR and SHR-mtBN conplastic rat strains: the effect of chronic hypoxia
JF - The Journal of Physiological Sciences
DO - 10.1007/s12576-017-0546-8
DA - 2017-05-31
UR - https://www.deepdyve.com/lp/springer-journals/adrenergic-signaling-monoamine-oxidase-a-and-antioxidant-defence-in-MVU8g0r0OQ
SP - 441
EP - 454
VL - 68
IS - 4
DP - DeepDyve
ER -