G protein-coupled estrogen receptor 1 (GPER-1) has gained recognition for its role in conferring cardioprotection. However, the extent to which GPER-1 exerts equally important effects in both sexes remains unclear. The study found similar expressions of GPER-1 in rat heart apex in both sexes. In male rats, administering epinephrine (Epi) at a dose of 31.36 microg/100 g resulted in a rapid decline in cardiac function, accompanied by a sharp increase in bax/bcl-2 levels. In contrast, female rats did not display significant changes in cardiac function under the same conditions. Additionally, compared to the injection of Epi alone (at a dose of 15.68 microg/100 g), the administration of G15 (GPER-1 antagonist) further decreased cardiac function in both male and female rats. However, it only increased mortality and lung coefficient in male rats. Conversely, G1 (GPER-1 agonist) administration improved cardiac function in both sexes. Notably, the apex of the male heart exhibited lower levels of inhibitory G protein (Galphai). Furthermore, female and male rats treated with Epi displayed elevated phosphorylated protein kinase B (p-Akt). Compared to their respective Epi groups, the administration of G15 increased p-Akt levels in female rat hearts but decreased them in male rat hearts. Conversely, the administration of G1 decreased p-Akt levels in females but rapidly increased them in male rats. Our study uncovers the vital role of GPER-1 in protecting against stress-induced heart injuries in a sex-specific manner. These findings hold immense potential for advancing targeted cardiac therapies and enhancing outcomes for both females and males.

Physiology Department Xuzhou Medical University Xuzhou China

References provided by Crossref.org