title: The natural PPAR agonist linoleic acid stimulated insulin release in the rat pancreas.
abstract: Free fatty acids play an important role in regulating animal insulin secretion response. Acute elevated free fatty acids increased animal insulin secretion and glucose-stimulated insulin secretion. In the present study, we perfused the rat pancreas to explore the effect of unsaturated fatty acids on insulin secretion. The results showed that linoleic acid, γ-linolenic acid and arachidonic acid significantly stimulated insulin secretion. Glucose (10 mM) alone induced a biphasic insulin secretion response. The peak effluent insulin concentrations increased by 444% and 800% compared with the baseline in the first and second insulin secretion phases, respectively. Based on comparison of the percentage increases, arachidonic acid, γ-linolenic acid or linoleic acid increased glucose-induced insulin release by 555% and 934%, 522% and 995% and 463% and 1,105% in the first and second insulin secretion phases, respectively. However, the percentage increases of insulin secretion decreased significantly to 402% and 564% in the first and second phases in the rats fed a high-fat diet for 13 weeks. Linoleic acid alone stimulated a 391% increase in the peak insulin concentration compared with the baseline in the rats fed a normal diet. The peak insulin concentration decreased significantly to 183% in the rats fed a long-term high-fat diet. All the results suggested that unsaturated fatty acids stimulated insulin secretion and additively increased glucose-induced insulin secretion in the perfused rat pancreas. However, the rats fed a high-fat diet had a decreased linoleic acid-induced insulin secretion response.
authors.affiliation: Department of Veterinary Medicine, College of Veterinary Medicine, National Chung Hsing University, No.250, Kuo Kuang Road, Taichung City, Taiwan 402, R.O.C.
authors.forename: Min-Chuan
authors.initials: MC
authors.lastname: Lai
authors.forename: Tzu-Hua
authors.initials: TH
authors.lastname: Teng
authors.forename: Chi
authors.initials: C
authors.lastname: Yang
mesh_terms: D000818:Animals; D019540:Area Under Curve; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D019787:Linoleic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D010179:Pancreas / Q000378:metabolism*; D047492:Peroxisome Proliferator-Activated Receptors / Q000819:agonists / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D007328:Insulin; D047492:Peroxisome Proliferator-Activated Receptors; D019787:Linoleic Acid