Abstract | BACKGROUND: Poor control of blood glucose in diabetes is known to promote vascular dysfunction and hypertension. Diabetes was recently shown to be linked to an increased prevalence of pulmonary hypertension. The aim of this study was to determine how the pharmacological reactivity of intrapulmonary arteries is altered in a rat model of diabetes. METHODS: RESULTS: STZ-induced diabetes significantly blunted the maximum response of conduit, but not resistance pulmonary arteries to phenylephrine and serotonin, without a change in pEC50. Agonist responses were differentially reduced, with serotonin (46% smaller) affected more than phenylephrine (32% smaller) and responses to PGF2alpha unaltered. Vasoconstriction caused by K+-induced depolarisation remained normal in diabetic rats. Endothelium-dependent dilation to carbachol and endothelium-independent dilation to glyceryl trinitrate were also unaffected. CONCLUSION: The small resistance pulmonary arteries are relatively resistant to STZ-induced diabetes. The impaired constrictor responsiveness of conduit vessels was agonist dependent, suggesting possible loss of receptor expression or function. The observed effects cannot account for pulmonary hypertension in diabetes, rather the impaired reactivity to vasoconstrictors would counteract the development of pulmonary hypertensive disease.
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Authors | Alison M Gurney, Frank C Howarth |
Journal | Cardiovascular diabetology
(Cardiovasc Diabetol)
Vol. 8
Pg. 4
(Jan 21 2009)
ISSN: 1475-2840 [Electronic] England |
PMID | 19159454
(Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Vasoconstrictor Agents
- Vasodilator Agents
- Phenylephrine
- Serotonin
- Streptozocin
- Carbachol
- Dinoprost
- Nitroglycerin
- Potassium
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Topics |
- Animals
- Calcium Signaling
(drug effects)
- Carbachol
(pharmacology)
- Diabetes Mellitus, Experimental
(physiopathology)
- Diabetic Angiopathies
(complications, physiopathology)
- Dinoprost
(pharmacology)
- Endothelium, Vascular
(drug effects, physiopathology)
- Hypertension, Pulmonary
(etiology)
- Male
- Membrane Potentials
(drug effects)
- Muscle, Smooth, Vascular
(drug effects, physiopathology)
- Nitroglycerin
(pharmacology)
- Phenylephrine
(pharmacology)
- Potassium
(pharmacology)
- Pulmonary Artery
(drug effects, physiopathology)
- Pulmonary Circulation
(drug effects)
- Rats
- Rats, Wistar
- Serotonin
(pharmacology)
- Streptozocin
- Vascular Resistance
(drug effects, physiology)
- Vasoconstrictor Agents
(pharmacology)
- Vasodilator Agents
(pharmacology)
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