Temporal patterns of alterations in obesity index, lipid profile, renal function and blood pressure during the development of hypertension in male, but not female, rats fed a moderately high-fat diet

Abstract

Context

Male Sprague-Dawley rats consuming a moderately high-fat (MHF)-diet diverge into obesity-prone (OP) with hypertension and obesity-resistant.

Objectives

To study the temporal inter-relationships between body-weight, obesity-index, plasma lipid-profile, renal functional parameters and systolic-pressure alterations during 10-weeks feeding MHF or normal diet to male and female rats.

Methods

Body-weight, obesity-index and systolic-pressure were measured weekly, while metabolic-cage and blood-sampling protocols were performed every other week. After 10-weeks, renal excretory responses to acute salt-loading and renal autoregulation were examined.

Results

The male-OP group had progressively increased body-weight, plasma-triglyceride and systolic-pressure from Weeks 2, 4 and 5, respectively, lower renal sodium-excretion at weeks 4–8 and finally, delayed excretory response to salt-loading and rightward and downward shifts in renal autoregulatory curves compared to all other groups.

Conclusion

Feeding the MHF-diet in male-OP rats led to a greater weight-gain and adiposity followed by the development of atherogenic-hyperlipidaemia and persistently impaired pressure-natriuresis to induce hypertension.

Keywords:

• Lipid profile
• obesity-induced hypertension
• obesity-prone
• pressure-natriuresis
• renal autoregulation

Acknowledgments

The authors thank Mrs R. Keshtkaran for her contribution in measuring plasma lipids as well as plasma and urine creatinine, urea and glucose in biochemistry laboratory of the Shahid Faghihi hospital.

Disclosure statement

The authors state no conflict of interest.

Additional information

Funding

The authors acknowledge the Vice-Chancellery for Research affairs of Shiraz University of Medical Sciences, Shiraz, Iran, for the financial support of this study as part of the thesis of S. Nazari for acquiring Ph.D. degree in physiology [grant number 1396–01-01–14439].