Long-term 24-hour rest-activity pattern of sheep in stalls and in the field

Summary Motor activity of sheep was continuously recorded for 2–3 weeks with an ambulatory monitoring device. Recordings were obtained from free-ranging animals in the field and from animals maintained under various controlled conditions in stalls. The sheep were diurnal under all conditions. While the daily amount of activity and the frequency of rest episodes showed only small differences between the conditions, the rest-activity pattern showed prominent differences. The pattern differed particularly between the field and the stalls. In the field, activity started to increase one hour after dawn, reaching a first maximum towards noon; a second, higher peak in the evening was followed by a rapid decline after dusk. In the stalls the onset and offset of activity was more abrupt; activity peaks coincided with feeding and human activity; the onset of rest with lights off. Activity was lowest and rest most prominent in those stalls where the animals were most isolated from human influence.     

Long-term 24-hour rest-activity pattern of sheep in stalls and in the field

Motor activity of sheep was continuously recorded for 2-3 weeks with an ambulatory monitoring device. Recordings were obtained from free-ranging animals in the field and from animals maintained under various controlled conditions in stalls. The sheep were diurnal under all conditions. While the daily amount of activity and the frequency of rest episodes showed only small differences between the conditions, the rest-activity pattern showed prominent differences. The pattern differed particularly between the field and the stalls. In the field, activity started to increase one hour after dawn, reaching a first maximum towards noon; a second, higher peak in the evening was followed by a rapid decline after dusk. In the stalls the onset and offset of activity was more abrupt; activity peaks coincided with feeding and human activity; the onset of rest with lights off. Activity was lowest and rest most prominent in those stalls where the animals were most isolated from human influence.     

Superoxide dismutase activity in the Spanish population

Summary Superoxide dismutase is an enzyme that catalyzes the dismutation of superoxide radicals to hydrogen peroxide and molecular oxygen. This superoxide radical is produced by all aerobic cells as a normal metabolic intermediate of molecular oxygen, and is dangerous for the cell because it induces the inactivation of various enzymes, lipid peroxidation and mutations. Superoxide dismutase can therefore be considered as a protective enzyme. The purpose of this work was to determine the level of superoxide dismutase activity in the Spanish population, and to study the factors that influence this activity. The superoxide dismutase activity of 2397 individuals was determined using the method described by Minami and Yoshikawa. The superoxide dismutase activity level in the adult Spanish population was found to be 4.16±0.89 Units/ml of blood. No significant variations with respect to sex were detected. But it was observed that the superoxide dismutase activity level was 9% higher in the young urban Spanish population.     

Superoxide dismutase activity in the Spanish population

Superoxide dismutase is an enzyme that catalyzes the dismutation of superoxide radicals to hydrogen peroxide and molecular oxygen. This superoxide radical is produced by all aerobic cells as a normal metabolic intermediate of molecular oxygen, and is dangerous for the cell because it induces the inactivation of various enzymes, lipid peroxidation and mutations. Superoxide dismutase can therefore be considered as a protective enzyme. The purpose of this work was to determine the level of superoxide dismutase activity in the Spanish population, and to study the factors that influence this activity. The superoxide dismutase activity of 2397 individuals was determined using the method described by Minami and Yoshikawa. The superoxide dismutase activity level in the adult Spanish population was found to be 4.16 +/- 0.89 Units/ml of blood. No significant variations with respect to sex were detected. But it was observed that the superoxide dismutase activity level was 9% higher in the young urban Spanish population.     

Species-specific differences in the mitogenic activity of heparin-binding growth factors in the sera of various mammals

Sera from different mammalian species displayed great differences in mitogenic activity, as measured by stimulation of DNA synthesis in BALB/c 3T3 cells (3T3 cells). Among the sera examined, fetal bovine serum was least active, and increasing activity was detected in calf serum, human serum, rat serum and mouse serum, in that order. Rat and mouse sera exhibited extremely high mitogenic activity with 3T3 cells, but when TIG-1 human fetal lung fibroblasts were used for the DNA assay instead, the activity levels of all of the sera were lower, and the differences between them were smaller. To determine the reasons for these differences, the heparin-binding growth factors in each serum were separated on a heparin affinity column. Five peaks of DNA-stimulating activity were obtained. Three of these were found in all sera examined, with both 3T3 cells and TIG-1 cells. Two other peaks were found only with 3T3 cells; one was peculiar to rat and mouse sera, with extremely high activity in the rat, and the other was specific to fetal serum. The dependence of the activity of these peaks on the cells used for the test was confirmed using normal rat lung fibroblasts and immortalized rat kidney cells. These findings adequately explain the species-specific differences in mitogenic activity of whole sera, and the variation in activity depending on the cells used for assay of DNA synthesis.     

Species-specific differences in the mitogenic activity of heparin-binding growth factors in the sera of various mammals.

Sera from different mammalian species displayed great differences in mitogenic activity, as measured by stimulation of DNA synthesis in BALB/c 3T3 cells (3T3 cells). Among the sera examined, fetal bovine serum was least active, and increasing activity was detected in calf serum, human serum, rat serum and mouse serum, in that order. Rat and mouse sera exhibited extremely high mitogenic activity with 3T3 cells, but when TIG-1 human fetal lung fibroblasts were used for the DNA assay instead, the activity levels of all of the sera were lower, and the differences between them were smaller. To determine the reasons for these differences, the heparin-binding growth factors in each serum were separated on a heparin affinity column. Five peaks of DNA-stimulating activity were obtained. Three of these were found in all sera examined, with both 3T3 cells and TIG-1 cells. Two other peaks were found only with 3T3 cells; one was peculiar to rat and mouse sera, with extremely high activity in the rat, and the other was specific to fetal serum. The dependence of the activity of these peaks on the cells used for the test was confirmed using normal rat lung fibroblasts and immortalized rat kidney cells. These findings adequately explain the species-specific differences in mitogenic activity of whole sera, and the variation in activity depending on the cells used for assay of DNA synthesis.     

Effect of light at night on the pineal rhythm in N-acetyltransferase activity in the Syrian hamsterMesocricetus auratus

Summary Pineal N-acetyltransferase activity in the male Syrian hamster exhibited a daily rhythm; the maximal night-time value was 3.5-fold higher than the day-time value. When hamsters were exposed to light at night N-acetyltransferase declined within 30 min to 1/5 of its former activity. These results indicate that in the Syrian hamster the pineal melatonin rhythm may be regulated at least partly via changes in N-acetyltransferase activity.The authors are grateful to Mrs Marie Svobodová for her skillful technical assistance.     

Fucosidosis and blood group substances in the urine]

Glycopeptide and oligosaccharide fractions obtained from fucosidosis urine contains more Lea activity (4-8 fold) than control urine. Both fucosidosis fractions also contained Leb and H activities, no A activity in contrast to the salivary and erythrocyte phenotypes (A, Le a+ b-). The amount of Leb activity is lower in both fractions (1) and (2) than that of Leb control children (4-16 fold decrease). Blood group A activity was not detected at any concentration used (less than or equal to 50 fold-concentrated urine) whereas A activity was found in (A, Le a- b+) control urine. On the contrary, both fucosidosis fractions contained H activity, whereas A (Le a- b+) control children fractions had none (less than or equal to 50-fold concentrated urine). H and Leb activity might originate from Lea precursor apart from the "non-secretory" type of the patient.     

Interaction of glucocorticosteroids with glucagon in the control of argininosuccinase activity in the fetal rat liver]

Exogenous glucagon, but not glucocorticosteroids cause a rise in argininosuccinase activity in the liver of 21.5 day old fetuses. When fetuses are deprived of glucocorticosteroids, glucagon is unable to promote the enzymic activity. This study indicates that glucocorticosteroids are required for the induction of the argininosuccinase activity by glucagon.     

Demonstration of N-acetylgalactosaminyltransferase activity in the murine lymphoma YC8]

The N-acetyl-galactosaminyltransferase activity has been studied in the biological fluids of YC8-lymphoma bearing Balb/c mice. It is enhanced during tumor development from 1 to 30 times in peritoneal fluids and from 1 to 10 times in sera. This activity is nil in urines. Optimal requirements for activity have been determined. Results suggest the existence, during tumor process not only of an enhancement of enzymatic activity, but also of a new molecule synthesis, molecules which are endogenous acceptors for the enzyme.     

Increased activity of dipeptidyl peptidase IV in serum of hepatoma-bearing rats coincides with the loss of the enzyme from the hepatoma plasma membrane

Summary The specific activity of dipeptidyl peptidase IV (DPPIV E.C. 3.4.14.-) in the plasma membrane of Morris hepatoma 9121 or hepatoma 7777 was 3.5% and 2.9%, respectively, of that in the plasma membrane of rat liver. The enzyme activity in the serum of hepatoma-bearing rats was 141% (hepatoma 91219) and 162% (hepatoma 7777) of the normal value. cytochemical investigation showed that the DPP IV activity was almost completely absent from the hepatoma cell plasma membrane and was not sequestered within these cells. Indirect immunofluorescence staining with a polyclonal antibody directed against DPP IV indicated that the loss of activity was due to the absence of DPP IV molecules in the plasma membrane. The possibility that the enzyme is transferred from the membrane into the serum as a result of structural alterations is discussed.     

Changes in the distribution of gamma-glutamyl transferase in the organs of the mouse as a function of development]

In the Mouse, gamma-glutamyl transferase distribution changes with development in the kidney and the liver; on the contrary, its activity remains almost equal and low in other organs. In the liver, a low activity is observed in the fetus and the new-born up to the 3rd day of life; then it is no more measurable. In the kidney, the low enzyme activity of the fetus is multiplied by 10 in the 10 first days of life and by 50 in the 6 first weeks.     

Development of thyroid peroxidase activity during the early stage of iodine deficiency in the hypophysectomized rat]

The iodide-peroxidase activity of the thyroid gland remains, in hypophysectomized Rats maintained on a low iodine diet, below normal value. This result suggests that the early increase of peroxidase activity observed in control Rats maintained on a low iodine diet is TSH dependent.     

Development and hormonal control of thioredoxin and the thioredoxin-reductase system in the rat liver during the perinatal period

The development and hormonal regulation of thioredoxin and of the thioredoxin-reductase system were investigated during the perinatal period in rat liver. An immunological procedure was developed in order to quantify thioredoxin in fetal and neonatal hepatocytes. Both immunoreactive thioredoxin and thioredoxin-reductase activity appeared on day 16.5 of pregnancy. The level of immunoreactive thioredoxin increased during the late fetal period, and its level was the same 24 h after birth. Moreover, its development was not subjected to hormonal regulation by corticosteroids and glucagon. In contrast, thioredoxin-reductase activity increased 3 times during the late fetal period and presented a marked increase 24 h after birth. In the absence of glucocorticoids there was no increase in the level of thioredoxin reductase, while administration of hydrocortisone acetate and glucagon to fetuses prematurely evoked its activity. This study suggests that if thioredoxin acts physiologically, this activity is related to the state of reduction of the molecule rather than to the total concentration in the liver.     

Metabolic implications in the elevation of serum activity of intestinal alkaline phosphatase in chronic renal failure

Summary The activity of intestinal isoenzyme of serum alkaline phosphatase was evaluated in 21 non-dialyzed patients with advanced renal failure and in 52 patients on regular hemodialysis. In patients without hepatopathy, a significant inverse correlation was found between the enzyme activity and serum calcium levels. Hepatopathy was the most significant variable influencing the enzyme activity in patients on dialysis. Secondary hyperparathyroidism and a decreased rate in enzyme elimination should be assessed for the above-normal activities of intestinal ALP in serum in chronic renal failure.     

Increased activity of dipeptidyl peptidase IV in serum of hepatoma-bearing rats coincides with the loss of the enzyme from the hepatoma plasma membrane

The specific activity of dipeptidyl peptidase IV (DPP IV E.C. 3.4.14.-) in the plasma membrane of Morris hepatoma 9121 or hepatoma 7777 was 3.5% and 2.9%, respectively, of that in the plasma membrane of rat liver. The enzyme activity in the serum of hepatoma-bearing rats was 141% (hepatoma 91219) and 162% (hepatoma 7777) of the normal value. Cytochemical investigation showed that the DPP IV activity was almost completely absent from the hepatoma cell plasma membrane and was not sequestered within these cells. Indirect immunofluorescence staining with a polyclonal antibody directed against DPP IV indicated that the loss of activity was due to the absence of DPP IV molecules in the plasma membrane. The possibility that the enzyme is transferred from the membrane into the serum as a result of structural alterations is discussed.     

Distribution of the a blood-group activity in porcine serum

Summary The A blood-group activity of pig serum is bound to a lipid, in some cases also to a nonlipid fraction. The major lipidic A activity (roughly 50%) is carried with the HDL class, while the VLDL and LDL classes contain roughly 25% each.This work was supported by Forschungsmittel des Landes Niedersachsen.     

Metabolic implications in the elevation of serum activity of intestinal alkaline phosphatase in chronic renal failure

Summary The activity of intestinal isoenzyme of serum alkaline phosphatase was evaluated in 21 non-dialyzed patients with advanced renal failure and in 52 patients on regular hemodialysis. In patients without hepatopathy, a significant inverse correlation was found between the enzyme activity and serum calcium levels. Hepatopathy was the most significant variable influencing the enzyme activity in patients on dialysis. Secondary hyperparathyroidism and a decreased rate in enzyme elimination should be assessed for the above-normal activities of intestinal ALP in serum in chronic renal failure.     

Metabolic implications in the elevation of serum activity of intestinal alkaline phosphatase in chronic renal failure

The activity of intestinal isoenzyme of serum alkaline phosphatase was evaluated in 21 non-dialyzed patients with advanced renal failure and in 52 patients on regular hemodialysis. In patients without hepatopathy, a significant inverse correlation was found between the enzyme activity and serum calcium levels. Hepatopathy was the most significant variable influencing the enzyme activity in patients on dialysis. Secondary hyperparathyroidism and a decreased rate in enzyme elimination should be assessed for the above-normal activities of intestinal ALP in serum in chronic renal failure.     

Metabolic implications in the elevation of serum activity of intestinal alkaline phosphatase in chronic renal failure

The activity of intestinal isoenzyme of serum alkaline phosphatase was evaluated in 21 non-dialyzed patients with advanced renal failure and in 52 patients on regular hemodialysis. In patients without hepatopathy, a significant inverse correlation was found between the enzyme activity and serum calcium levels. Hepatopathy was the most significant variable influencing the enzyme activity in patients on dialysis. Secondary hyperparathyroidism and a decreased rate in enzyme elimination should be assessed for the above-normal activities of intestinal ALP in serum in chronic renal failure.