A high-potassium diet reduces infarct size and improves vascular structure in hypertensive rats

Anne M. Dorrance, David M. Pollock, Olga P. Romanko, David W Stepp

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

High-potassium diets can improve vascular function, yet the effects of potassium supplementation on ischemic stroke have not been studied. We hypothesized that dietary potassium supplementation would reduce ischemic cerebral infarct size by reversing cerebral artery hypertrophy. Six-week-old male stroke-prone spontaneously hypertensive rats (SHRSP) were fed diets containing 0.79% potassium (LK) or 2.11% potassium (HK) for 6 wk; Wistar-Kyoto (WKY) rats were fed the LK diet. The HK diet did not reduce blood pressure, as measured by telemetry, in the SHRSP. Cerebral ischemia was induced by middle cerebral artery (MCA) occlusion. The resultant infarct was smaller in the HK-SHRSP than in the LK-SHRSP: 55.1 ± 6.3 vs. 71.4 ± 2.4% of the hemisphere infarcted (P < 0.05). Infarcts were smaller in WKY rats (33.5 ± 4.8%) than in LK-SHRSP or HK-SHRSP. The vessel wall of MCAs from LK-SHRSP was hypertrophied compared with WKY rats; this was reversed in HK-SHRSP. RT-PCR analysis of the cerebral vessels showed that expression of platelet-derived growth factor receptors-α and -β, epidermal growth factor receptor, and collagen I and III was increased in the vessels from LK-SHRSP compared with WKY rats and reduced in HK-SHRSP. These results suggest that potassium supplementation provides neuroprotection in a model of ischemic stroke independent of blood pressure and possibly through changes in vascular structure.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume292
Issue number1
DOIs
StatePublished - Jan 1 2007

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Inbred WKY Rats
Blood Vessels
Potassium
Diet
Stroke
Dietary Potassium
Blood Pressure
Platelet-Derived Growth Factor Receptors
Telemetry
Cerebral Arteries
Middle Cerebral Artery Infarction
Inbred SHR Rats
Dietary Supplements
Brain Ischemia
Epidermal Growth Factor Receptor
Hypertrophy
Collagen
Polymerase Chain Reaction

Keywords

  • Cerebral ischemia
  • Growth factors
  • Middle cerebral artery occlusion
  • Smooth muscle cells
  • Spontaneously hypertensive rats

ASJC Scopus subject areas

  • Physiology

Cite this

A high-potassium diet reduces infarct size and improves vascular structure in hypertensive rats. / Dorrance, Anne M.; Pollock, David M.; Romanko, Olga P.; Stepp, David W.

In: American Journal of Physiology - Regulatory Integrative and Comparative Physiology, Vol. 292, No. 1, 01.01.2007.

Research output: Contribution to journalArticle

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