title: Alteration of the cardiac sympathetic innervation is modulated by duration of diabetes in female rats.
abstract: To evaluate the sympathetic innervation of the female diabetic heart, resting heart rate and sympathetic tone were assessed in vivo, and effect of tyramine on spontaneous beating rate, norepinephrine atrial concentrations, uptake, and release were determined in vitro in streptozotocin- (STZ-) treated rats and respective controls aged 3 months to 2 years. Resting bradycardia, decreased sympathetic tone, deceleration of spontaneous beating rate, and slightly declining carrier-mediated, but preserved exocytotic norepinephrine release from the atria were found in younger diabetic rats while the reactivity of the right atria to tyramine was not affected with age and disease duration. Diabetic two-year-old animals displayed symptoms of partial spontaneous recovery including normoglycemia, increased plasma insulin concentrations, fully recovered sympathetic tone, but putative change, in releasable norepinephrine tissue stores. Our data suggested that female diabetic heart exposed to long-lasting diabetic conditions seems to be more resistant to alteration in sympathetic innervation than the male one.
authors.affiliation: Department of Physiology, Faculty of Medicine in Plzeň, Charles University, Lidická 1, 301 00 Plzeň, Czech Republic.
authors.forename: Jitka
authors.initials: J
authors.lastname: Švíglerová
authors.forename: Jiří
authors.initials: J
authors.lastname: Mudra
authors.forename: Zbyněk
authors.initials: Z
authors.lastname: Tonar
authors.forename: Jana
authors.initials: J
authors.lastname: Slavíková
authors.forename: Jitka
authors.initials: J
authors.lastname: Kuncová
mesh_terms: D000818:Animals; D001285:Atropine / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology*; D005260:Female; D006321:Heart / Q000187:drug effects / Q000294:innervation* / Q000503:physiopathology; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007328:Insulin / Q000378:metabolism; D008297:Male; D014290:Metipranolol / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D012727:Sex Characteristics; D013311:Streptozocin; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology*; D013565:Sympatholytics / Q000494:pharmacology; D013997:Time Factors
chemical_list: D007328:Insulin; D013565:Sympatholytics; D013311:Streptozocin; D001285:Atropine; D014290:Metipranolol