Biomaterial Database

Effect of L-triiodothyronine on liver microsomal delta 6 and delta 5 desaturase activity of male rats. 1993

A Ves-Losada, and R O Peluffo

Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET-UNLP, Facultad de Ciencias Médicas, Argentina.

The effect of different doses of L-triiodothyronine (T3) on the activity of delta 6 and delta 5 desaturases and lipid fatty acid composition was studied in liver microsomes of male rats. The activity of delta 6 and delta 5 desaturases was decreased 24 and 28%, respectively, in animals administered a daily intraperitoneal dose of 1000 micrograms T3/100 g body wt. for 5 days, whereas with 500 micrograms T3/100 g body wt. only delta 6 desaturase activity was decreased. On the other hand, no enzyme activity changed at a shorter period of hormone treatment. Changes in microsomal fatty acid composition did not seem to be a direct consequence of desaturation activity, since after 1 and 5 days of T3 treatment, the concentrations of 18:2 (n-6) and 20:3 (n-6) decreased and only after 1 day that of 20:4 (n-6) increased in spite of unchanged or decreased delta 6 and delta 5 desaturase activities. Other factors than desaturation activity must be involved in fatty acid composition of thyroid hormone-treated rats, such as diet, membrane lipid synthesis and degradation, fatty acid turn-over and oxidation.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008862	Microsomes, Liver	Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.	Liver Microsomes,Liver Microsome,Microsome, Liver
D000090943	Delta-5 Fatty Acid Desaturase	A fatty acid desaturase that is a rate-limiting enzyme for the conversion from dihomo-gamma-linolenic acid and EICOSATETRAENOATE (ETA) in the synthesis of ARACHIDONIC ACID and EICOSAPENTAENOATE (EPA). It is also involved in the biosynthesis of unsaturated fatty acids from the polyunsaturated fatty acids (PUFA), LINOLEIC ACID (LA), and ALPHA LINOLENIC ACID (ALA) precursors and plays an important role in the metabolism of inflammatory lipids including PROSTAGLANDIN E2.	Delta 5 Desaturase,Delta-5-FADase,Fatty Acid Delta-5-Desaturase,5 Desaturase, Delta,Acid Delta-5-Desaturase, Fatty,Delta 5 FADase,Delta-5-Desaturase, Fatty Acid,Desaturase, Delta 5,Fatty Acid Delta 5 Desaturase
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014284	Triiodothyronine	A T3 thyroid hormone normally synthesized and secreted by the thyroid gland in much smaller quantities than thyroxine (T4). Most T3 is derived from peripheral monodeiodination of T4 at the 5' position of the outer ring of the iodothyronine nucleus. The hormone finally delivered and used by the tissues is mainly T3.	Liothyronine,T3 Thyroid Hormone,3,3',5-Triiodothyronine,Cytomel,Liothyronine Sodium,Thyroid Hormone, T3
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats
D044943	Fatty Acid Desaturases	A family of enzymes that catalyze the stereoselective, regioselective, or chemoselective syn-dehydrogenation reactions. They function by a mechanism that is linked directly to reduction of molecular OXYGEN.	Acyl CoA Desaturase,Enoyl CoA Reductase,Fatty Acid Desaturase,Fatty Acid Desaturating Enzymes,Acyl CoA Desaturases,Enoyl CoA Reductases,Acid Desaturase, Fatty,CoA Desaturase, Acyl,CoA Reductase, Enoyl,Desaturase, Acyl CoA,Desaturase, Fatty Acid,Desaturases, Fatty Acid,Reductase, Enoyl CoA,Reductases, Enoyl CoA
D050602	Linoleoyl-CoA Desaturase	An enzyme that catalyzes the syn-dehydrogenation of linoleol-CoA gamma-linolenoyl-CoA. It was formerly characterized as EC 1.14.99.25.	Delta(6)-Desaturase,Delta-6 Fatty Acid Desaturase,Delta-6-Desaturase,Delta-6-FADTase,Fatty Acid Delta-6-Desaturase,Linoleic Acid Delta-6 Desaturase,Linoleoyl CoA Desaturase,Linoleoyl Coenzyme A Desaturase,Acid Delta-6-Desaturase, Fatty,CoA Desaturase, Linoleoyl,Delta 6 Desaturase,Delta 6 FADTase,Delta 6 Fatty Acid Desaturase,Delta-6-Desaturase, Fatty Acid,Desaturase, Linoleoyl CoA,Desaturase, Linoleoyl-CoA,Fatty Acid Delta 6 Desaturase,Linoleic Acid Delta 6 Desaturase
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus