Salameh Bweir


Diabetes Mellitus has been linked to vascular and neurological impairments. The purpose of this study was to assess the relationship between vascular endothelial dysfunction, autonomic and somatic nervous systems impairment in diabetic patients. These studies also evaluated the effects of rosiglitazone (Avandia) on the vascular, autonomic, and somatic nervous systems.

Fourteen diabetic subjects and fourteen control subjects (age matched) participated in three series of experiments. Using Whitney volume plesythmography to assess post occlusion blood flow in the subject’s forearm did assessment of vascular endothelial function. Evaluating skin blood flow, orthostatic tolerance, heart rate, and thermal responses under thermal and postural stress did assessment of the autonomic nervous system reactivity. Evaluating the subject’s gait assessed the function of the somatic nervous system.

The results of this study showed significant impairment of vascular endothelial function in the diabetic subjects when compared to the control subjects (P < 0.01). Four weeks after administration of rosiglitazone, there was a rapid and significant improvement in vascular endothelial function (P < 0.01).

There was a significant impairment in skin blood flow, sweat rate, skin temperature, core temperature, and orthostatic tolerance during heat exposure in subjects with diabetes. After 4 weeks of rosiglitazone administration, there was a gradual but significant improvement in skin blood flow and sweat rate. Core temperature, skin temperature, and heart rate showed no significant changes after 4 weeks of administration of rosiglitazone (P < 0.05). Orthostatic tolerance showed significant improvement in the diabetic subjects after administration of rosiglitazone (P < 0.05). In terms of gait, diabetic patients showed significantly shorter steps and slower gait, and more tremors at the knees than the control subjects. No administration of rosiglitazone was in this group.

In conclusion, diabetic patients have showed impairment in vascular endothelial function, which rapidly improved after administration of rosiglitazone for 4 weeks. This improvement may be due that, rosiglitazone increasing nitric oxide production and inhibit PARP activity. The sequence of the improvement in the autonomic nervous system after rosiglitazone indicates that the healing took place in two steps: a rapid improvement in microcirculation and a slower improvement in autonomic function. Impairment of gait velocity and stability demonstrate that diabetic subjects suffer from somatic nervous system impairment.

LLU Discipline

Rehabilitation Sciences


Rehabilitation Sciences


Graduate School

First Advisor

Jerrold Petrofsky

Second Advisor

Michael Laymon

Third Advisor

Scott Lee

Fourth Advisor

Everett Loham III

Fifth Advisor

Ernie Schwab

Degree Name

Doctor of Philosophy (PhD)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Diabetes Mellitus -- drug therapy; Diabetes Complications; Thiazolidinediones -- therapeutic use; Nervous System -- pathology; Cardiovascular System -- pathology.



Page Count

xi; 121

Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

Collection Website


Loma Linda University. Del E. Webb Memorial Library. University Archives