Search PubMed⌕ Search

Biomedical subjects

M Morrison

Publications and source records attributed to M Morrison.

At least 181 records · Page 10Linked to original sources
PubMed1967

Genetic control of lactate dehydrogenase formation in the hagfish Eptatretus stoutii.

The isozyme patterns of lactate dehydrogenases of various tissues were studied on 51 hagfish by starch-gel electrophoresis. Nine lactate dehydrogenase phenotypes were encountered, suggesting the coexistence of two alleles at each of the two separate gene loci. There apparently was no interaction between the products of these two separate loci. Even the products of two alleles at the same locus were apparently incapable of forming hybrid molecules, an indication of the possible monomeric nature of each lactate dehydrogenase molecule.

Animals↗
PubMed1966

Multiple gene loci for the monomeric hemoglobin of the hagfish (Eptatretus stoutii).

The fact that members of the subclass Cyclotomata possess monomeric hemoglobin molecules has been known for some time. Electrophoresis of hemolysates from 12 hagfish (Eptatretus stoutii) revealed five hemoglobin phenotypes with four to six distinct zones of hemoglobin. Each zone is believed to represent a monomer containing one heme group on a single polypeptide chain with a molecular weight of approximately 18,000. It is postulated that these monomers are controlled by genes at four loci.

Animals↗
PubMed1966

Hexose-6-phosphate dehydrogenase found in human liver.

Starch-gel electrophoresis of extracts of human liver revealed the presence of a new hexose-6-phosphate dehydrogenase that was slower-moving at pH 8.6 than the sex-linked glucose-6-phosphate dehydrogenase. When the gel plate was stained, galactose-6-phos phate being used as a substrate, this enzyme band stained intensely, but the sex-linked glucose-6-phosphate dehydro genase failed to stain. This new human enzyme may well be homologous with the autosomally inherited glucose-6-phosphate dehydrogenase of the deer mouse (Peromyscus maniculatus), re ported by Shaw and Barto.

Adolescent↗
PubMed1966

Lactoperoxidase: identification and isolation from Harderian and lacrimal glands.

Investigation of bovine lacrimal and harderian glands revealed the presence of the enzyme lactoperoxidase, which was isolated and purified. A nonheme, iron-containing protein was identified at the same time. Both proteins are present in milk, mammary glands, and salivary glands. Their roles are discussed: The lactoperoxidase may be important in controlling bacterial flora.

Animals↗
PubMedDate not supplied

Plasma GABA, GABA-like activity and the brain GABA-benzodiazepine receptor complex in rats with chronic hepatic encephalopathy.

Plasma gamma-aminobutyric acid (GABA)-like activity, plasma GABA and the brain GABA-benzodiazepine receptor complex were studied in rats with chronic hepatic encephalopathy. Portal vein ligation (after prior subcutaneous transposition of the spleen) results in complete portal bypass of splanchnic blood. In addition, significant hepatocellular damage was superimposed on this model of portosystemic shunting by ligation of the common bile duct. Plasma GABA-like activity (determined by radioreceptor assay) and true plasma GABA concentrations (determined by high-performance liquid chromatography) were found to be significantly increased in both portal vein-ligated and portal vein and bile duct-ligated rats, compared with controls. However, plasma GABA-like activity was consistently greater than the concentration of true GABA in the plasma of all rats. This suggested the presence of a GABA-like factor in plasma that can inhibit [3H]GABA binding, but is not GABA itself. The concentration of this GABA-like factor was significantly increased in the plasma of rats with chronic hepatic encephalopathy. Despite the significant increase in plasma GABA-like activity and plasma GABA concentrations, there was no alteration in the affinity or density of the physiologically relevant, low-affinity brain GABA binding site in the rats with portal vein ligation, with or without bile duct ligation. There was also no significant alteration in brain benzodiazepine binding in these rats. GABA enhancement of benzodiazepine binding was unchanged in the portal vein-ligated rats. However, the maximal enhancement of benzodiazepine binding was decreased in the rats with portal vein and bile duct ligation. There appears to be no substantial evidence that brain GABAergic neurotransmission is increased in these models of chronic hepatic encephalopathy.

Animals↗