The effectiveness of treatments of diabetic autonomic neuropathy is not the same in autonomic nerves supplying different organs.
The aim of the study was to investigate antioxidant (alpha-lipoic acid [LA]) and gamma-linolenic acid treatments in the prevention of changes in autonomic nerves induced in streptozotocin-diabetic rats. Autonomic nerves supplying the heart, penis, and gut were examined using immunohistochemical and biochemical techniques. LA and gamma-linolenic acid (present in evening primrose oil [EPO]) were administered as dietary supplements ( approximately 80 and 200 mg. kg(-1). day(-1), respectively). LA treatment prevented the diabetes-induced decrease of norepinephrine (NA) in the heart and of type I nitric oxide synthase (NOS-I) expression in erectile tissue of the penis but failed to prevent diabetes-induced changes in NA-, vasoactive intestinal polypeptide-, or calcitonin gene-related peptide-containing nerves supplying the ileum. LA partially prevented and EPO totally prevented the increase in NOS-I activity induced by diabetes in the ileum. EPO treatment failed to prevent any other diabetes-induced changes in the heart, penis, or ileum. These results demonstrate that, whereas LA treatment is more effective than EPO in preventing diabetes-induced changes in autonomic nerves, the effectiveness of LA treatment varies with the target organ studied. Diabetes-induced changes in nerves supplying the ileum are more resistant to treatment than those of the heart and penis.
Shotton
Hannah R
HR
Department of Anatomy and Developmental Biology, Autonomic Neuroscience Institute, Royal Free and University College Medical School, London, U.K.
Clarke
Simon
S
Lincoln
Jill
J
D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D001342:Autonomic Nervous System Diseases / Q000517:prevention & control*; D017776:Autonomic Pathways / Q000378:metabolism; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D003929:Diabetic Neuropathies / Q000188:drug therapy*; D006329:Heart Conduction System; D008297:Male; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I; D009638:Norepinephrine / Q000378:metabolism; D010413:Penis / Q000294:innervation; D051381:Rats; D017208:Rats, Wistar; D008063:Thioctic Acid / Q000627:therapeutic use*; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism; D017965:gamma-Linolenic Acid / Q000627:therapeutic use*
D000975:Antioxidants; D014660:Vasoactive Intestinal Peptide; D008063:Thioctic Acid; D017965:gamma-Linolenic Acid; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; C496322:Nos1 protein, rat; D015740:Calcitonin Gene-Related Peptide; D009638:Norepinephrine