title: Limited acute influences of electrical baroreceptor activation on insulin sensitivity and glucose delivery: a randomized, double-blind, crossover clinical study.
abstract: Arterial baroreflexes may regulate resistance vessels supplying glucose to skeletal muscle by modulating efferent sympathetic nervous system activity. We hypothesized that selective manipulation of baroreflex activity through electrical carotid sinus stimulation influences insulin sensitivity by changing muscular glucose delivery. We enrolled 16 hypertensive patients who responded to treatment with an electrical carotid sinus stimulator. Patients were submitted to a frequently sampled intravenous glucose tolerance test (FSIGT) with the stimulator on and with the stimulator off on separate days in a randomized, double-blind, crossover study. We monitored interstitial glucose, lactate, and pyruvate in the vastus lateralis muscle using microdialysis. Glucose and insulin concentrations in arterialized venous blood before and during FSIGT were virtually identical with the stimulator on and with the stimulator off. Insulin sensitivity, the primary end point of this study, was 3.3 ± 1.0 (mU/L)(-1) ⋅ min(-1) and 4.4 ± 2.6 (mU/L)(-1) ⋅ min(-1) (on vs. off; P = 0.7). Interstitial glucose, lactate, and pyruvate increased similarly during FSIGT regardless of the stimulator settings. In conclusion, acute changes in baroreceptor stimulation did not elicit significant changes in muscular glucose delivery and whole-body insulin sensitivity. Baroreflex-mediated changes in sympathetic vasomotor tone may have a limited acute effect on muscle glucose metabolism in patients with treatment-resistant hypertension.
authors.affiliation: Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: May
authors.affiliation: Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany.
authors.forename: Jelka
authors.initials: J
authors.lastname: Ahrens
authors.affiliation: Department of Nephrology and Hypertension, Hannover Medical School, Hannover, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Menne
authors.affiliation: Department of Nephrology and Hypertension, Hannover Medical School, Hannover, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Haller
authors.affiliation: Department of Nephrology, St. Georg Clinic, Leipzig, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Beige
authors.affiliation: Heart and Diabetes Center Nodrhein-Westfalen, Bad Oeynhausen, Germany.
authors.forename: Siegfried
authors.initials: S
authors.lastname: Eckert
authors.affiliation: Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Jordan
authors.affiliation: Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany engeli.stefan@mh-hannover.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Engeli
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004558:Electric Stimulation / Q000379:methods; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D006973:Hypertension; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D011311:Pressoreceptors / Q000502:physiology*
chemical_list: D005947:Glucose