Synergistic effects of C-peptide and insulin on coronary flow in early diabetic rats

• Published in: Metabolism, clinical and experimental clinical and experimental, 2004-03, Vol.53 (3), p.335-339
• Main Authors: Nakamoto, Hiroshi, Sakane, Naoki, Kimura, Kazuhiro, Yoshida, Toshihide, Mochizuki, Seiichi, Ogasawara, Yasuo, Kajiya, Fumihiko
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; C-Peptide - pharmacology; Cardiology. Vascular system; Coronary Circulation - drug effects; Coronary heart disease; Diabetes Mellitus, Experimental - drug therapy; Diabetes Mellitus, Experimental - physiopathology; Diabetes. Impaired glucose tolerance; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Heart; Hypoglycemic Agents - pharmacology; Insulin - blood; Insulin - pharmacology; Male; Medical sciences; Nitric Oxide - biosynthesis; Rats; Rats, Wistar
• ISSN: 0026-0495; 1532-8600
• DOI: 10.1016/j.metabol.2003.10.014

The aims of the present study are (1) to examine whether coronary flow is increased and (2) to examine the role of C-peptide in relation to nitric oxide (NO) production and coronary flow in a rat heart (Wistar) during the early stages of type 1 diabetes. Coronary flow increased by 36.4% ±10.6% ( P < .05) during the early stages of streptozotocin-induced diabetes of isolated perfused rat hearts, but NO production increased without significance. C-peptide alone did not change coronary flow, but increased NO production in diabetes. In the presence of insulin, C-peptide reversed both flow and NO production to the control level of normal rats ( P < .05). In conclusion, during the early stages of type 1 diabetes, coronary flow was increased, and C-peptide in the presence of insulin synergistically normalized the excessive flow and NO production induced by C-peptide to the control level of normal rats.