Title |
Augmented Endothelial-Specific L-Arginine Transport Blunts the Contribution of the Sympathetic Nervous System to Obesity Induced Hypertension in Mice
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Published in |
PLOS ONE, July 2015
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DOI | 10.1371/journal.pone.0131424 |
Pubmed ID | |
Authors |
Niwanthi W. Rajapakse, Florian Karim, Roger G. Evans, David M. Kaye, Geoffrey A. Head |
Abstract |
Augmenting endothelial specific transport of the nitric oxide precursor L-arginine via cationic amino acid transporter-1 (CAT1) can prevent obesity related hypertension. We tested the hypotheses that CAT1 overexpression prevents obesity-induced hypertension by buffering the influence of the sympathetic nervous system (SNS) on the maintenance of arterial pressure and by buffering pressor responses to stress. Wild type (WT; n=13) and CAT1 overexpressing mice (CAT+; n=13) were fed a normal or a high fat diet for 20 weeks. Mice fed a high fat diet were returned to the control diet before experiments commenced. Baseline mean arterial pressure (MAP) and effects of restraint-, shaker- and almond feeding-stress and ganglionic blockade (pentolinium; 5 mg/kg; i.p.) on MAP were determined in conscious mice. Fat feeding increased body weight to a similar extent in WT and CAT+ but MAP was greater only in WT compared to appropriate controls (by 29%). The depressor response to pentolinium was 65% greater in obese WT than lean WT (P < 0.001), but was similar in obese and lean CAT+ (P = 0.65). In lean WT and CAT+, pressor responses to shaker and feeding stress, but not restraint stress, were less in the latter genotype compared to the former (P ≤ 0.001). Pressor responses to shaker and feeding stress were less in obese WT than lean WT (P ≤ 0.001), but similar in obese and lean CAT+. The increase in MAP in response to restraint stress was less in obese WT (22 ± 2%), but greater in obese CAT+ (37 ± 2%), when compared to respective lean WT (31 ± 3%) and lean CAT+ controls (27 ± 2%; P ≤ 0.02). We conclude that CAT1 overexpression prevents obesity-induced hypertension by reducing the influence of the SNS on the maintenance of arterial pressure but not by buffering pressor responses to stress. |
Mendeley readers
Geographical breakdown
Country | Count | As % |
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Unknown | 17 | 100% |
Demographic breakdown
Readers by professional status | Count | As % |
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Student > Master | 5 | 29% |
Student > Postgraduate | 2 | 12% |
Professor | 1 | 6% |
Lecturer | 1 | 6% |
Student > Ph. D. Student | 1 | 6% |
Other | 1 | 6% |
Unknown | 6 | 35% |
Readers by discipline | Count | As % |
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Pharmacology, Toxicology and Pharmaceutical Science | 2 | 12% |
Veterinary Science and Veterinary Medicine | 2 | 12% |
Biochemistry, Genetics and Molecular Biology | 1 | 6% |
Nursing and Health Professions | 1 | 6% |
Other | 3 | 18% |
Unknown | 5 | 29% |