Journal of Physiology and Biochemistry

, Volume 71, Issue 2, pp 165–175 | Cite as

Investigation of changes in apelin receptor mRNA and protein expression in the myocardium and aorta of rats with two-kidney, one-clip (2K1C) Goldblatt hypertension

  • Hamid Najafipour
  • Abedin Vakili
  • Beydolah Shahouzehi
  • Ava Soltani Hekmat
  • Yaser Masoomi
  • Mahbobeh Yeganeh Hajahmadi
  • Saeed Esmaeli-Mahani
Original Paper


Experimental and clinical evidences suggest that apelin and its receptor APJ are involved in the pathogenesis of cardiovascular complications. However, the role of apelin/APJ in hypertension is not sufficiently understood. Because chronic kidney diseases lead to hypertension and cardiac failure, we investigated the changes in apelin receptor gene expression in the myocardium and aorta of rat models of kidney disease hypertension. Two-kidney, one-clip (2K1C) hypertension was produced by placing a clip around the renal artery. Four and 16 weeks later, blood pressure, left ventricular end-diastolic pressure (LVEDP), serum apelin, and angiotensin II were measured. The messenger RNA (mRNA) and protein of APJ were determined by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting. Chronic hypertensive rats had approximately 10 times higher LVEDP (P < 0.001). 2K1C decreased serum apelin from 220 ± 11 to 170 ± 10 pg/mL in 16 weeks (P < 0.05). The mRNA expression of APJ significantly decreased in the heart and aorta at 4 weeks. At 16 weeks, the reduction was not significant in the heart but was significant in the aorta. At 4 weeks, the expression of the APJ protein significantly decreased in the heart but not in the aorta. At 16 weeks, APJ protein was significantly decreased only in the aorta. Reduction of serum apelin and downregulation of apelin receptors in both the heart and aorta may play a role in the pathophysiology of hypertension and cardiac failure in 2K1C hypertensive rats.


Renovascular hypertension Apelin receptor Heart Aorta Gene expression 



This work was supported by grants from the Iran National Science Foundation—INSF (Grant No. 92029227) and the Physiology Research Center of Semnan University of Medical Sciences, Semnan, Iran. The authors are thankful to Zahra Kordestani and Sara Araghsoltan from the Kerman Physiology Research Center and Zahra Hajializadeh from the Kerman Neuroscience Research Center for their technical support in laboratory tests.

Conflict of interest

The authors declare that they have no conflict of interests.


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Copyright information

© University of Navarra 2015

Authors and Affiliations

  • Hamid Najafipour
    • 1
  • Abedin Vakili
    • 2
  • Beydolah Shahouzehi
    • 3
  • Ava Soltani Hekmat
    • 4
  • Yaser Masoomi
    • 1
  • Mahbobeh Yeganeh Hajahmadi
    • 3
  • Saeed Esmaeli-Mahani
    • 5
  1. 1.Physiology Research Center, Institute of NeuropharmacologyKerman University of Medical SciencesKermanIran
  2. 2.Physiology Research CenterSemnan University of Medical SciencesSemnanIran
  3. 3.Cardiovascular Research Center, Institute of Basic and Clinical Physiology SciencesKerman University of Medical SciencesKermanIran
  4. 4.Department of PhysiologyFasa University of Medical SciencesFasaIran
  5. 5.Department of BiologyShahid Bahonar UniversityKermanIran

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