PS 13-30 ROUX-EN-Y GASTRIC BYPASS SURGERY AMELIORATES HIGH BLOOD PRESSURE THROUGH ANTAGONIZING OVERDRIVE OF THE SYMPATHETIC NERVE

Abstract

Objective: Roux-en-Y Gastric Bypass (RYGB) Surgery can effectively prevent cardiometabolic dysfunction, however its mechanism is little known. We investigated the hypothesis that the favorable effects on hypertension (HTN) and cardiovascular (CV) disturbances are mediated by antagonizing overdrive of the sympathetic nervous system (SNS). Design and Method: Hypertensive patients with metabolic disturbances underwent laparoscopic RYGB surgery, and spontaneously hypertensive rats (SHRs) underwent RYGB or sham surgery. Blood pressure (BP), heart rate (HR), endothelium-dependent flow-mediated dilation, and anthropometric as well as laboratory parameters were measured at baseline and during follow-up. Changes of BP and HR in response to cold stress, renal sympathetic nervous activity (RSNA), vasoconstriction induced by electrical field stimulation, microinjection of nucleus of the solitary tract (NTS), and CV function and structure were examined in SHRs with or without surgery. Results: Compared with baseline, BP and HR were significantly reduced in both hypertensive patients with type 2 diabetes and rats. Impaired endothelial-dependent vasodilatation and metabolic disturbances in hypertensive patients were also ameliorated after surgery. CV disturbances were reversed by surgery in SHRs. Under acute cold exposure, the variations in BP and HR were smaller in surgically treated SHRs, compared to sham SHRs. RSNA and vasoconstriction induced by perivascular nerve stimulation as well as NTS-mediated changes of BP were decreased in surgically treated SHRs, compared to sham SHR. Weight loss did not affect BP and RSNA in sham SHRs. Conclusions: RYGB surgery ameliorates HTN in both hypertensive patients and rats by inhibiting overdrive of the SNS. Therefore, targeting gastrointestine could be a novel strategy to treat HTN with metabolic disturbances.