Sex differences in rat renal arterial responses following exercise training

• Published in: American journal of physiology. Heart and circulatory physiology Vol. 322; no. 2; p. H310
• Main Authors: Vezér, Márton, Demeter, Ágota, Szekeres, Mária, Jósvai, Attila, Bányai, Bálint, Oláh, Attila, Balogh, Fruzsina, Horváth, Eszter M, Radovits, Tamás, Merkely, Béla, Ács, Nándor, Nádasy, György L, Török, Marianna, Várbíró, Szabolcs
• Format: Journal Article
• Language: English
• Published: United States 01-02-2022
• Subjects: Acetylcholine - pharmacology; Actins - metabolism; Animals; Cholinergic Agonists - pharmacology; Cyclooxygenase Inhibitors - pharmacology; Elastin - metabolism; Female; Indomethacin - pharmacology; Male; Phenylephrine - pharmacology; Physical Conditioning, Animal - methods; Rats; Rats, Wistar; Renal Artery - drug effects; Renal Artery - metabolism; Renal Artery - physiology; Sex Characteristics; Swimming; Vasoconstriction; Vasoconstrictor Agents - pharmacology; renal artery; decreased vasoconstriction; immunohistochemistry; sex differences; exercise training
• ISSN: 1522-1539
• DOI: 10.1152/ajpheart.00398.2021

During aerobic exercise, hemodynamic alterations occur. Although blood flow in skeletal muscle arteries increases, it decreases in visceral vessels because of mesenterial vasoconstriction. However, maintaining renal blood flow during intensive sport is also a priority. Our aim was to investigate the changes of vascular reactivity and histology of isolated renal artery of male and female rats in response to swim training. Wistar rats were distributed into four groups: male sedentary (MSed), male trained (MTr), female sedentary (FSed), and female trained (FTr). Trained animals underwent a 12-wk-long intensive swimming program. Vascular function of isolated renal artery segments was examined by wire myography. Phenylephrine-induced contraction was lower in FSed than in MSed animals, and it was decreased by training in male but not in female animals. Inhibition of cyclooxygenases by indomethacin reduced contraction in both sedentary groups, and in MTr but not in FTr animals. Inhibition of nitric oxide production increased contraction in both trained groups. Acetylcholine induced relaxation was similar in all experimental groups showing predominant NO-dependency. Elastin and smooth muscle cell actin density was reduced in female rats after aerobic training. This study shows that, as a result of a 12-wk-long training, there are sex differences in renal arterial responses following exercise training. Swimming moderates renal artery vasoconstriction in male animals, whereas it depresses elastic fiber and smooth muscle actin density in females.
We provided the first detailed analysis of the adaptation of the renal artery after aerobic training in male and female rats. As a result of a 12-wk-long training program, the pharmacological responses of renal arteries changed only in male animals. In phenylephrine-induced contraction, cyclooxygenase-mediated vasoconstriction mechanisms lost their significance in female rats, whereas NO-dependent relaxation became a significant contraction reducing factor in both sexes. Early structural changes, such as reduced elastin and smooth muscle cell actin evolves in females.