Adrenomedullary Response to Glucagon in Patients with Primary Sjögren’s Syndrome

Abstract

Several studies showed signs of autonomic dysfunction in patients with primary Sjögren's syndrome (pSS). Adrenomedullary function might be of importance for pSS pathogenesis by affecting salivary gland functions and modulating immune responses. The aim of the study was to evaluate the adrenomedullary hormonal system in patients with pSS. The glucagon test (1 mg i.v.) was performed in 18 pSS patients and 13 control subjects. During the test each patient had electrocardiographic and impedance cardiographic monitoring. Plasma epinephrine and norepinephrine were assayed by liquid chromatography with electrochemical detection after batch alumina extraction. Baseline concentrations of epinephrine and norepinephrine were comparable between pSS and controls. Glucagon administration induced a significant increase in systolic blood pressure, diastolic blood pressure, heart rate, cardiac output (P < 0.01), and stroke volume; however, the changes were comparable between pSS and controls. Epinephrine levels increased (P < 0.01) in response to glucagon administration while norepinephrine concentration did not change. There was no significant difference in neurochemical responses to glucagon between pSS and controls. In conclusion, the present results suggest normal adrenomedullary function in pSS.