Biomedical subjects

P Morata

Publications and source records attributed to P Morata.

29 records · Page 2Linked to original sources

PubMed1989

Effect of low-iodine diet and propylthiouracil on glycolytic enzymes in brain areas of adult rats.

Glycolytic activity of five brain areas in the rat was studied under two hypothyroid states: (1) induced by low-iodine diet from weaning, and (2) induced by propylthiouracil. The areas studied were the anterior cortex, amygdala, hypothalamus, septum and hippocampus. A low-iodine diet induced a decrease of pyruvate kinase activity in three region and of phosphofructokinase in the hippocampus, while hexokinase increased in both the amygdala and septum. Propylthiouracil treatment produced an increase in hexokinase activity in the hypothalamus and septum, and a decrease in the anterior cortex, while phosphofructokinase decreased significantly in the hippocampus. No significant changes of lactate dehydrogenase activity were observed. The correlation between the results and type of hypothyroidism is discussed.

Animals↗

PubMed1989

Fructose bisphosphatase activity in the serum of rats treated with carbon tetrachloride.

In this work, fructose bisphosphatase activity in the serum of rats treated by different carbon tetrachloride doses was measured. Fructose bisphosphatase activity increased very significantly with respect to the control animals in all groups assayed. The severe reduction of the activity measured in the presence of adenosine-5'-monophosphate and its stability when measured in the presence of 1-p-bromotetramisole oxalate support its specific origin. These data suggest that serum FBPase activity measurement could be used as a biochemical marker in the diagnosis of hepatocellular injury.

Animals↗

PubMed1987

Activities of glycolytic enzymes in some brain areas of thyroidectomized rats and their response to replacement therapy.

Glycolytic metabolism has been assessed by studying a set of key enzymes, in anterior cortex, amygdala, hypothalamus septum and hippocampus, in thyroidectomized rats. The reversibility of the changes induced by the thyroidectomy has been assessed by replacement therapy. In thyroidectomized rats the hexokinase activity was significantly decreased in anterior cortex and hypothalamus. The increase in phosphofructokinase and pyruvate kinase activity was probably due to an increase in cellular energy requirements. Hexokinase activity was best restored by treatment with L-thyroxine (T4) or T4+ propylthiouracil (PTU). The low response of pyruvate kinase activity in all treated animals could suggest that this metabolic step is the least reversible.

Animals↗

PubMed1987

Influence of thyroid hormone deficiency on the citrate synthase activity in rat brain regions during early postnatal development.

The developmental pattern of citrate synthase activity has been studied in the liver and several brain areas of hypothyroid rats during the 4 first weeks of life. While citrate synthase activity in the liver showed a rise during the 2 first weeks of life, different patterns of enzyme activity were found in the brain regions of euthyroid animals. Citrate synthase activity increased in the cerebellum, decreased in the cerebral cortex and did not change significantly in the brain stem during the period studied. In the liver and brain areas, too, a decrease in citrate synthase activity was observed during hypothyroidism. From the 2nd week of birth, the citrate synthase activity in the brain but not in the liver was found to have recovered. The newly elevated citrate synthase activity coincided with a slight increase in thyroid hormone serum levels.

Animals↗

PubMed1986

[Changes in dehydrogenase glutamate in the rat brain caused by thyroid hormone deficiency].

The dependent GDH-NADPH activity in adenohypophysis and other cerebral areas, has been studied in hypothyroid rats, in which hypothyroidism has been induced surgically. After thyroidectomy a decrease of GDH activity in limbic system (amygdala, septum and hippocampus), and an increase of this enzyme in cortex and hypothalamus have been found, with no changes in adenohypophysis. The alterations of GDH activity, induced by thyroidectomy, have been corrected, although not uniformly in the different brain areas after L-T3 treatment.

Animals↗

PubMed1985

Effect of thyroid hormones on the glycolytic enzyme activity in brain areas of the rat.

The glycolytic metabolism through the key enzymes, hexokinase, phosphofructokinase, pyruvate kinase and lactate dehydrogenase, have been studied in the brain areas: anterior cortex, amygdala, hypothalamus, septum and hippocampus in adult rats with pharmacologically induced hyperthyroidism. The oxidative metabolism of glucose is accelerated in most brain areas by treatment with high doses of T3, as is shown by the increase in HK activity, approaching normality on reducing the dose. This decrease can also by observed in the PFK activity through the effect of assayed doses of thyroxine. The anterior cortex is the only brain area that does not show significant variations of PK activity through the effects of treatment with thyroid hormones. On the other hand, a general inhibition of the glycolytic anaerobic pathway by treatment with T3 was observed.

Amygdala↗

PubMed1985

[Effect of thyroid hormones on the activity of pyruvate kinase and lactate dehydrogenase in mature rat brain].

The enzymatic activities of two "key" enzymes of the glycolytic pathway, pyruvate kinase and lactic dehydrogenase, were studied in seven areas of the brain in male adult rats in states of pharmacologically induced hyper and hypothyroidism. The brain areas were: anterior cortex, adenohypophysis, hypothalamus, amygdaline nucleus, septum, hippocampus and cerebellum. In T3 treated animals, pyruvate kinase activity showed significant increase in all the areas studied while lactic dehydrogenase activity decreased. In propyl-thiouracil treated animals these enzyme activities showed no significant variations from those in animals of the control group.

Animals↗

PubMed1982

Evolution of gluconeogenic enzyme activities during starvation in liver and kidney of the rainbow trout (Salmo gairdneri).

1. There was a general increase in the activities of enzymes involved in gluconeogenesis in liver and kidney of rainbow trout, Salmo gairdneri, during the second month of starvation. 2. The need of gluconeogenesis during the first month of the starvation period was probably minimal because of the utilization of liver glycogen as a source of blood glucose. 3. The decline of fat was more pronounced than that of protein total content in absolute values, suggesting that lipid reserved were the main sources of energy during starvation.

Animals↗

PubMed1982

Hormonal effects on the liver glucose metabolism in rainbow trout (Salmo gairdneri).

1. Glucagon, adrenaline and dibutyril cyclic AMP increased the release of glucose to the medium during incubation of liver slices from rainbow trout (Salmo gairdneri) while insulin had no effect. 2. Glycogen content decreased only slightly after cyclic AMP addition and even increased in the presence of glucagon and adrenaline. Consequently, the release of glucose was due mainly to gluconeogenesis. 3. This is corroborated by the reduction of glucose liberation in presence of alpha-cyanocinnamate, an inhibitor of gluconeogenesis.

Animals↗

PubMed1979

[Evolution of liver and kidney gluconeogenesis during acute liver intoxication by carbon tetrachloride (author's transl)].

Evolution of early renal metabolic adaptation to the rat liver intoxication by carbon tetrachloride is studied. Liver glycogen is very rapidly depleted (20% of initial values at 3 h) and liver gluconeogenic capacity is completely inhibited 7 h after carbon tetrachloride treatment. Contrariwise, a gradual enhancement of phosphoenolpyruvate carboxikinase activity and gluconeogenic capacity of kidney cortex takes place during this period. Accordingly, renal concentrations of aspartate, malate, and phosphoenolpyruvate indicate that the reaction catalysed by phosphoenolpyruvate carboxykinase is accelerated in vivo. These findings suggest that metabolic adaptation of kidney cortex in response to liver functional impairment plays an important role early after carbon tetrachloride administration.

Animals↗

PubMedDate not supplied

Influence of thyroid hormone deficiency in DNA contents in different areas of adult rat brain.

We have studied DNA concentrations in various regions of the adult rat brain in prolonged hypothyroidism of different origin. In both normal and hypothyroid rats hypophysis, cerebellum and hypothalamus contained the highest concentrations of DNA. Hypothyroidism produced a slight decrease in DNA content but this effect varied according to the different regions. These variations were due to changes in their maturation period, a critical and specific target for thyroid hormone action after birth.

Animals↗