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Activation of GPER ameliorates experimental pulmonary hypertension in male rats.

ABSTRACT: RATIONALE:Pulmonary hypertension (PH) is characterized by pulmonary vascular remodeling that leads to pulmonary congestion, uncompensated right-ventricle (RV) failure, and premature death. Preclinical studies have demonstrated that the G protein-coupled estrogen receptor (GPER) is cardioprotective in male rats and that its activation elicits vascular relaxation in rats of either sex. OBJECTIVES:To study the effects of GPER on the cardiopulmonary system by the administration of its selective agonist G1 in male rats with monocrotaline (MCT)-induced PH. METHODS:Rats received a single intraperitoneal injection of MCT (60mg/kg) for PH induction. Experimental groups were as follows: control, MCT+vehicle, and MCT+G1 (400?g/kg/daysubcutaneous). Animals (n=5pergroup) were treated with vehicle or G1 for 14days after disease onset. MEASUREMENTS AND MAIN RESULTS:Activation of GPER attenuated exercise intolerance and reduced RV overload in PH rats. Rats with PH exhibited echocardiographic alterations, such as reduced pulmonary flow, RV hypertrophy, and left-ventricle dysfunction, by the end of protocol. G1 treatment reversed these PH-related abnormalities of cardiopulmonary function and structure, in part by promoting pulmonary endothelial nitric oxide synthesis, Ca2+ handling regulation and reduction of inflammation in cardiomyocytes, and a decrease of collagen deposition by acting in pulmonary and cardiac fibroblasts. CONCLUSIONS:G1 was effective to reverse PH-induced RV dysfunction and exercise intolerance in male rats, a finding that have important implications for ongoing clinical evaluation of new cardioprotective and vasodilator drugs for the treatment of the disease.

SUBMITTER: Alencar AK

PROVIDER: S-EPMC5183553 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Activation of GPER ameliorates experimental pulmonary hypertension in male rats.

Alencar Allan K AK Montes Guilherme C GC Montagnoli Tadeu T Silva Ananssa M AM Martinez Sabrina T ST Fraga Aline G AG Wang Hao H Groban Leanne L Sudo Roberto T RT Zapata-Sudo Gisele G

European journal of pharmaceutical sciences : official journal of the European Federation for Pharmaceutical Sciences 20161109

<h4>Rationale</h4>Pulmonary hypertension (PH) is characterized by pulmonary vascular remodeling that leads to pulmonary congestion, uncompensated right-ventricle (RV) failure, and premature death. Preclinical studies have demonstrated that the G protein-coupled estrogen receptor (GPER) is cardioprotective in male rats and that its activation elicits vascular relaxation in rats of either sex.<h4>Objectives</h4>To study the effects of GPER on the cardiopulmonary system by the administration of its ...[more]

PMID: 27836751

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Activation of GPER ameliorates experimental pulmonary hypertension in male rats.

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Activation of GPER ameliorates experimental pulmonary hypertension in male rats.

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