Neuropeptide Y and CGRP concentrations in the rat tail artery: Effects of age and two types of diabetes

• Published in: Peptides (New York, N.Y. : 1980) N.Y. : 1980), 2009-04, Vol.30 (4), p.710-714
• Main Authors: Morrison, J.F.B., Dhanasekaran, S., Howarth, F.C.
• Format: Article
• Language: English
• Subjects: Aging; Amines; Animals; Arteries - metabolism; Autonomic nervous system; Biological and medical sciences; Blood Glucose - analysis; Calcitonin Gene-Related Peptide - metabolism; Diabetes; Diabetes Mellitus, Experimental - metabolism; Diabetes Mellitus, Type 1 - metabolism; Diabetes Mellitus, Type 2 - metabolism; Diabetes. Impaired glucose tolerance; Disease Models, Animal; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Fundamental and applied biological sciences. Psychology; Goto-Kakizaki rats; Male; Medical sciences; Neuropathy; Neuropeptide Y - metabolism; Peripheral nervous system. Autonomic nervous system. Neuromuscular transmission. Ganglionic transmission. Electric organ; Rats; Rats, Wistar; Streptozocin; Streptozotocin; Sympathetic nervous system; Tail - blood supply; Tail artery; Vertebrates: endocrinology; Vertebrates: nervous system and sense organs
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/j.peptides.2008.11.013

The changes in concentrations of two neuropeptides, neuropeptide Y (NPY) and calcitonin gene-related peptide (CGRP) in different segments of the rat tail artery have been investigated (a) after 12 and 16 weeks of streptozotocin (STZ)-induced hyperglycemia that has been induced at the age of 10 weeks, and (b) in 52-week-old Goto-Kakizaki (GK) rats that were intolerant of glucose, and age-matched Wistar controls. In the control animals at 22, 26 and 52 weeks of age, the concentration of CGRP was significantly greater in distal, relative to proximal, segments of normal arteries, and this contrasted with the pattern of distribution of NPY, which was consistently greater in the proximal than the distal segments. STZ-induced diabetes caused significant reductions in the concentrations of NPY and CGRP in the middle and distal segments of the vessel after 12 and 16 weeks of hyperglycemia. In the glucose-intolerant Goto-Kakizaki (GK) rats, the noradrenalin and adrenalin levels increased significantly in the distal segment of the artery relative to controls; in contrast there was a significant fall in dopamine concentration. The only significant change in the level of NPY in 52-week-old GK rats was an increase in the proximal segment, suggesting that in Type II pre-diabetes, noradrenalin and its co-transmitter NPY are affected independently. The concentration of CGRP increased significantly in all segments of the artery of the 12-month-old GK rats relative to controls. The similarities and differences between these measurements in Type I and Type II diabetic models are discussed.