Changes of fatty acid composition in incubated rat pancreatic islets.
The hypothesis that changes in fatty acId composition of pancreatic islets occur during incubation was investigated.



The content and composition of fatty acIds (FA) from rat pancreatic islets and culture medium after incubation for 1 and 3 hours in the absence or in the presence of 5.6, 8.3, or 16.7 mM glucose were determined by HPLC analysis.



The FA content of pancreatic islets was reduced after 1 hour incubation in the absence of glucose. However, the total FA content was restored by incubating in the presence of 5.6 mM glucose and exceeded by incubating in the presence of 8.3 mM or 16.7 mM glucose. Saturated FA contributed a substantially greater proportion of the total FA increase in comparison to unsaturated FA, being palmitic and stearic acIds the most important. The total lipId content of pancreatic islets was not increased if the period of incubation in the presence of glucose was extended to 3 hours. A substantial amount of FA was found in the medium after 1 hour incubation in the absence of glucose: 141 ng per 80 islets for saturated and 75 ng per 80 islets for unsaturated. The release of FA from islets is increased in the presence of glucose.



The release of FA from islets is a novel finding and may be related to modulation of B-cell function.
Martins
E F
EF
Center of Biological Sciences and Health, University of Cruzeiro do Sul, São Paulo, SP, Brazil. edgair@fisio.icb.usp.br
Miyasaka
C K
CK
Newsholme
P
P
Curi
R
R
Carpinelli
A R
AR
D000818:Animals; D002851:Chromatography, High Pressure Liquid; D005230:Fatty Acids, Nonesterified / Q000302:isolation & purification / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000302:isolation & purification / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D051381:Rats; D017208:Rats, Wistar
D005230:Fatty Acids, Nonesterified; D005231:Fatty Acids, Unsaturated; D005947:Glucose