Biomaterial Database

Intra-acinar profiles of cytosolic and mitochondrial malate dehydrogenase isoenzymes in rat liver. 1994

I P Maly, and M Toranelli, and D Sasse

Anatomisches Institut, Universität Basel, Switzerland.

A new method for electrophoretic separation of the isoforms of malate dehydrogenase in microdissected tissue samples was applied to rat liver. The intra-acinar activity profiles of cytosolic (cMDH) and mitochondrial (mMDH) malate dehydrogenase were determined in male and female control animals and in animals fasted for 84 hr. Measurements were carried out on lyophilized liver tissue samples of 50-100 ng from the whole length of the sinusoid. The results showed that both in fed and fasted animals, mMDH activity was almost evenly distributed throughout the acinus in livers of both sexes. cMDH showed higher activity in the periportal area compared with the perivenous area by a factor of approximately 1.35 in all animals studied. Our results favor a slightly higher capacity of the malate-aspartate shuttle in the periportal area in both fed and fasted animals. Furthermore, the distribution pattern of mMDH suggests that this isoenzyme is not a marker for the zonation of the oxidative metabolism in the liver acinus.

UI	MeSH Term	Description	Entries
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D008291	Malate Dehydrogenase	An enzyme that catalyzes the conversion of (S)-malate and NAD+ to oxaloacetate and NADH. EC 1.1.1.37.	Malic Dehydrogenase,NAD-Malate Dehydrogenase,Dehydrogenase, Malate,Dehydrogenase, Malic,Dehydrogenase, NAD-Malate,NAD Malate Dehydrogenase
D008297	Male		Males
D008832	Microchemistry	The development and use of techniques and equipment to study or perform chemical reactions, with small quantities of materials, frequently less than a milligram or a milliliter.
D008930	Mitochondria, Liver	Mitochondria in hepatocytes. As in all mitochondria, there are an outer membrane and an inner membrane, together creating two separate mitochondrial compartments: the internal matrix space and a much narrower intermembrane space. In the liver mitochondrion, an estimated 67% of the total mitochondrial proteins is located in the matrix. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p343-4)	Liver Mitochondria,Liver Mitochondrion,Mitochondrion, Liver
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D004586	Electrophoresis	An electrochemical process in which macromolecules or colloidal particles with a net electric charge migrate in a solution under the influence of an electric current.	Electrophoreses
D005215	Fasting	Abstaining from FOOD.	Hunger Strike,Hunger Strikes,Strike, Hunger,Strikes, Hunger
D005260	Female		Females