+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Essential fatty acid deficiency and nutritional supplementation in cystic fibrosis



Essential fatty acid deficiency and nutritional supplementation in cystic fibrosis



Journal of Pediatrics 141(2): 157-159



In rat caudal artery, contraction to melatonin results primarily from activation of MT(1) melatonin receptors; however, the role of MT(2) melatonin receptors in vascular responses is controversial. We examined and compared the expression and function of MT(2) receptors with that of MT(1) receptors in male rat caudal artery. MT(1) and MT(2) melatonin receptor mRNA was amplified by reverse transcription-polymerase chain reaction from caudal arteries of three rat strains (i.e., Fisher, Sprague-Dawley, and Wistar). Antisense (but not sense) (33)P-labeled oligonucleotide probes specific for MT(1) or MT(2) receptor mRNA hybridized to smooth muscle, as well as intimal and adventitial layers, of caudal artery. In male Fisher rat caudal artery denuded of endothelium, melatonin was 10 times more potent than 6-chloromelatonin to potentiate contraction to phenylephrine, suggesting activation of smooth muscle MT(1) melatonin receptors. The MT(1)/MT(2) competitive melatonin receptor antagonist luzindole (3 microM), blocked melatonin-mediated contraction (0.1-100 nM) with an affinity constant (K(B) value of 157 nM) similar to that for the human MT(1) receptor. However, at melatonin concentrations above 100 nM, luzindole potentiated the contractile response, suggesting blockade of MT(2) receptors mediating vasorelaxation and/or an inverse agonist effect at MT(1) constitutively active receptors. The involvement of MT(2) receptors in vasorelaxation is supported by the finding that the competitive antagonists 4-phenyl 2-acetamidotetraline and 4-phenyl-2-propionamidotetraline, at MT(2)-selective concentrations (10 nM), significantly enhanced contractile responses to all melatonin concentrations tested (0.1 nM-10 microM). We conclude that MT(2) melatonin receptors expressed in vascular smooth muscle mediate vasodilation in contrast to vascular MT(1) receptors mediating vasoconstriction.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 034869343

Download citation: RISBibTeXText

PMID: 12183705

DOI: 10.1067/mpd.2002.126453


Related references

Persistence of essential fatty acid deficiency in cystic fibrosis despite nutritional therapy. Pediatric Research 66(5): 585-589, 2009

Essential fatty acid deficiency in the rabbit as a model of nutritional impairment in cystic fibrosis effects on alveolar macrophages. Pediatric Research 15(4 Part 2): 720, 1981

Essential fatty acid deficiency in the rabbit as a model of nutritional impairment in cystic fibrosis. In vitro and in vivo effects on lung defense mechanisms. American Review of Respiratory Disease 126(3): 540-547, 1982

Long chain fatty acid metabolism and essential fatty acid deficiency with special emphasis on cystic fibrosis. Bracco, U. And R. J. Deckelbaum (ed.). Nestle Nutrition Workshop Series, Vol. 28. Polyunsaturated Fatty Acids In Human Nutrition; Meeting, Mexico City, Mexico, November 27-30,. Xi 243p. Nestec Ltd: Vevey, Switzerland; Raven Press: New York, New York, Usa. Illus. 159-167, 1992

Essential fatty acid status in cystic fibrosis and the effects of safflower oil supplementation. American Journal of Clinical Nutrition 34(1): 1-7, 1981

Effect on renal function of essential fatty acid supplementation in cystic fibrosis. Journal of Pediatrics 115(2): 242-250, 1989

Hypothesis: vitamin E complements polyunsaturated fatty acids in essential fatty acid deficiency in cystic fibrosis. Journal of the American College of Nutrition 22(4): 253-257, 2003

Direct transesterification of plasma fatty acids for the diagnosis of essential fatty acid deficiency in cystic fibrosis. Journal of Lipid Research 30(10): 1483-1490, 1989

Essential fatty acid deficiency due to artificial diet in cystic fibrosis. British Medical Journal 2(5964): 192-193, 1975

Oral correction of essential fatty acid deficiency in cystic fibrosis. Jpen. Journal of Parenteral and Enteral Nutrition 5(6): 501-504, 1981

Essential fatty acid deficiency and the pathologic triene 20 3w9 in cystic fibrosis. Pediatric Research 29(4 Part 2): 110A, 1991

Ursodeoxycholic acid improves essential fatty acid deficiency in cystic fibrosis. Hepatology 18(4 Part 2): 271A, 1993

Lipoprotein metabolism in cystic fibrosis role of essential fatty acid deficiency. Gastroenterology 96(5 Part 2): A621, 1989

Essential fatty acid deficiency in relation to genotype in patients with cystic fibrosis. Journal of Pediatrics 139(5): 650-655, 2001

Essential fatty acid deficiency and predisposition to lung disease in cystic fibrosis. Acta Paediatrica 85(12): 1426-1432, 1996