Abstract

Hypertension is one of the most common risk factors in the development of heart disease, stroke and end stage renal failure. Sympathetic overactivity is believed to be one of the main mechanism behind resistant hypertension. Renal denervation has been used to treat resistant hypertension, although this procedure is an invasive one. Spinal cord stimulation (SCS) is a known modality to treat ischemic pain, angina pectoris, and peripheral vascular diseases. In previous studies in this laboratory, unilateral spinal cord stimulation in spontaneously hypertensive rat (SHR) at 67% of the motor threshold increased urinary sodium and water excretion significantly, without affecting mean arterial pressure (MAP) or renal blood flow. Bilateral spinal cord stimulation in spontaneously hypertensive rats (SHR) at 67% of the motor threshold at the level of T11 – T12 increased urinary sodium and water excretion significantly, while complete renal denervation eliminated the response. To further understand the mechanism by which dorsal spinal stimulation increases urinary sodium and water excretion, spinal stimulation was used in four groups of SHR, two intact and two with dorsal rhizotomy of the renal nerve. SCS was applied at 67% of motor threshold at the level of T11 – T12, to one group under each condition, intact or dorsal rhizotomized rats. SCS produced a significant increase from baseline in urinary sodium excretion in rats with intact renal nerves only. A similar increase was also observed when urine volume was analyzed. Dorsal rhizotomy alone produced a significant increase in urine volume, and a decrease in MAP in the rats also subjected to SCS. These results indicates that the natriuretic effect of SCS is dependent on the antidromic transmission of the electrical signal on the renal afferent nerves back to the kidney.

Advisor

Penny Knoblich

Committee Member

Michael Bentley

Committee Member

Rachel Cohen

Date of Degree

2019

Language

english

Document Type

Thesis

Degree

Master of Science (MS)

Department

Biological Sciences

College

Science, Engineering and Technology

Recommended Citation

Ahmed, T.T. (2019). The effect of dorsal rhizotomy on renal sodium excretion following dorsal spinal stimulation [Master's thesis, Minnesota State University, Mankato]. Cornerstone: A Collection of Scholarly and Creative Works for Minnesota State University, Mankato. https://cornerstone.lib.mnsu.edu/etds/969/