Exercise training improves arterial baro- and chemoreflex in control and diabetic rats

• Published in: Autonomic neuroscience Vol. 133; no. 2; pp. 115 - 120
• Main Authors: Harthmann, Angela D, De Angelis, Kátia, Costa, Luciana Parente, Senador, Danielle, Schaan, Beatriz D, Krieger, Eduardo Moacyr, Irigoyen, Maria-Cláudia
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30-05-2007; Elsevier
• Subjects: Advanced Basic Science; Animals; Autonomic dysfunction; Autonomic Nervous System Diseases - etiology; Autonomic Nervous System Diseases - physiopathology; Autonomic Nervous System Diseases - therapy; Baroreflex - physiology; Biological and medical sciences; Blood pressure; Blood Pressure - physiology; Bradycardia - physiopathology; Cardiovascular Diseases - physiopathology; Cardiovascular Diseases - prevention & control; Cardiovascular Diseases - therapy; Chemoreceptor Cells - physiology; Diabetes Complications - physiopathology; Diabetes Complications - prevention & control; Diabetes Complications - therapy; Diabetes Mellitus, Experimental; Diabetes. Impaired glucose tolerance; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Exercise Test - methods; Exercise Therapy - methods; Exercise training; Experimental diabetes; Fundamental and applied biological sciences. Psychology; Heart Rate - physiology; Male; Medical Education; Medical sciences; Peripheral nervous system. Autonomic nervous system. Neuromuscular transmission. Ganglionic transmission. Electric organ; Physical Conditioning, Animal - physiology; Rats; Recovery of Function - physiology; Tachycardia - physiopathology; Treatment Outcome; Vertebrates: nervous system and sense organs; Autonomic dysfunction; Blood pressure; Experimental diabetes; Exercise training; Endocrinopathy; Physical exercise; Chemoreflex; Rat; Diabetes mellitus; Rodentia; Vertebrata; Mammalia; Autonomic nervous system; Animal; Hemodynamics
• ISSN: 1566-0702; 1872-7484
• DOI: 10.1016/j.autneu.2006.10.004

Abstract We investigated the effect of exercise training on blood pressure, heart rate, and arterial baro- and chemoreflex sensitivity in diabetic rats (streptozotocin, 50 mg/kg iv). Male Wistar rats (251 ± 10 g) were divided into 4 groups ( n = 8, each group): sedentary normotensive (SC), sedentary diabetic (SD), trained normotensive (TC), and trained diabetic (TD). Trained groups underwent exercise training on a treadmill (10 weeks). Exercise training induced resting bradycardia (340 ± 5 vs. 316 ± 8 bpm) and improvement in baroreflex tachycardic response (3.4 ± 0.31 vs. 2.7 ± 0.06 bpm/mmHg in SC) and chemoreflex bradycardic (145 ± 12 vs. 78 ± 7 bpm in SC) and pressor (49 ± 5 vs. 22 ± 3 mmHg in SC) responses in control rats. Diabetic-induced hypotension (SC: 107 ± 2 vs. SD: 93 ± 2 mmHg) and bradycardia (SC: 340 ± 5 vs. SD: 276 ± 7 bpm) were reversed by exercise training. Baroreflex tachycardic and bradycardic responses impaired in SD rats (SD: 2.1 ± 0.18 and 1.3 ± 0.08 vs. SC: 2.7 ± 0.06 and 1.3 ± 0.08 bpm/mmHg) were enhanced in TD rats (2.5 ± 0.1 and 1.7 ± 0.06 bpm/mmHg). Chemoreflex bradycardic and pressor responses, attenuated in SD rats (23 ± 9 bpm and 7 ± 1 mmHg) in relation to SC rats, were improved by exercise (TD: 84 ± 15 bpm and 32 ± 5 mmHg). The improvement in arterial baro- and chemoreflex-mediated control of circulation in trained control and diabetic rats reinforces the role of exercise in the management of cardiovascular risk in healthy and diabetic individuals.