Biomaterial Database

Localization, cellular morphology and respiratory capacity of "brown" adipose tissue in newborn reindeer. 1992

P Soppela, and R Sormunen, and S Saarela, and P Huttunen, and M Nieminen

Finnish Game and Fisheries Institute, Reindeer Research, Rovaniemi, Finland.

1. The localization and cellular morphology of adipose tissue was studied by light, fluorescence and electron microscopy in reindeer between 2 weeks pre partum and 4.5 months post partum during calving, and the subsequent growth period. The respiratory capacity of the adipose tissue was examined in terms of morphometric mitochondrial volume and cytochrome-c oxidase or succinate dehydrogenase activity. 2. Adipose tissue was located at specific anatomical sites in the newborn reindeer (from 0 to 2 days of age). The perirenal-abdominal depot was the largest location (32%) followed by the inter(pre)scapular (18%) and sternal (12%) depots. Internal depot dominated over external or peripheral depots (66-34%). The locations of adipose tissue were largely similar in foetal, newborn and young reindeer. 3. The adipose tissue of the newborn reindeer had all the typical cell morphological characteristics of brown adipose tissue: abundant mitochondria, multilocular fat, high vascularization and a dense spot-like sympathetic innervation between the adipocytes. In the young reindeer, however, it resembled white adipose tissue, being almost totally unilocular with few mitochondria. 4. There was a significant correlation between morphometric mitochondrial volume and cytochrome-c oxidase activity (r = 0.848) in the adipose tissue. Mitochondrial volume, cytochrome-c oxidase and succinate dehydrogenase activity were highest after birth and decreased to almost an undetectable level during the first month. A parallel decrease occurred in the amount of brown adipose tissue from birth (1-2%) to the age of about one month (0.3%). 5. It is concluded that the distinct cell morphological features and high respiratory capacity of the adipose tissue indicate the presence of brown adipose tissue at specific anatomical locations in newborn reindeer. A marked progression towards the characteristics of white adipose tissue then takes place at the same locations during the first month. The results suggest the fundamental significance of brown adipose tissue for non-shivering thermogenesis in newborn reindeer.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008928	Mitochondria	Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Mitochondrial Contraction,Mitochondrion,Contraction, Mitochondrial,Contractions, Mitochondrial,Mitochondrial Contractions
D012053	Reindeer	A genus of deer, Rangifer, that inhabits the northern parts of Europe, Asia, and America. Caribou is the North American name; reindeer, the European. They are often domesticated and used, especially in Lapland, for drawing sleds and as a source of food. Rangifer is the only genus of the deer family in which both sexes are antlered. Most caribou inhabit arctic tundra and surrounding arboreal coniferous forests and most have seasonal shifts in migration. They are hunted extensively for their meat, skin, antlers, and other parts. (From Webster, 3d ed; Walker's Mammals of the World, 5th ed, p1397)	Caribou
D002001	Adipose Tissue, Brown	A thermogenic form of adipose tissue composed of BROWN ADIPOCYTES. It is found in newborns of many species including humans, and in hibernating mammals. Brown fat is richly vascularized, innervated, and densely packed with MITOCHONDRIA which can generate heat directly from the stored lipids.	Brown Fat,Hibernating Gland,Brown Adipose Tissue,Fat, Brown,Tissue, Brown Adipose
D003576	Electron Transport Complex IV	A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.	Cytochrome Oxidase,Cytochrome aa3,Cytochrome-c Oxidase,Cytochrome Oxidase Subunit III,Cytochrome a,a3,Cytochrome c Oxidase Subunit VIa,Cytochrome-c Oxidase (Complex IV),Cytochrome-c Oxidase Subunit III,Cytochrome-c Oxidase Subunit IV,Ferrocytochrome c Oxygen Oxidoreductase,Heme aa3 Cytochrome Oxidase,Pre-CTOX p25,Signal Peptide p25-Subunit IV Cytochrome Oxidase,Subunit III, Cytochrome Oxidase,p25 Presequence Peptide-Cytochrome Oxidase,Cytochrome c Oxidase,Cytochrome c Oxidase Subunit III,Cytochrome c Oxidase Subunit IV,Oxidase, Cytochrome,Oxidase, Cytochrome-c,Signal Peptide p25 Subunit IV Cytochrome Oxidase,p25 Presequence Peptide Cytochrome Oxidase
D005260	Female		Females
D000375	Aging	The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.	Senescence,Aging, Biological,Biological Aging
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
D000831	Animals, Newborn	Refers to animals in the period of time just after birth.	Animals, Neonatal,Animal, Neonatal,Animal, Newborn,Neonatal Animal,Neonatal Animals,Newborn Animal,Newborn Animals
D013385	Succinate Dehydrogenase	A flavoprotein containing oxidoreductase that catalyzes the dehydrogenation of SUCCINATE to fumarate. In most eukaryotic organisms this enzyme is a component of mitochondrial electron transport complex II.	Succinic Oxidase,Fumarate Reductase,Succinic Dehydrogenase,Dehydrogenase, Succinate,Dehydrogenase, Succinic,Oxidase, Succinic,Reductase, Fumarate