1,720,989 research outputs found
Liver cell proliferation induced by single administration of thiobenzamide.
No full textAfter administration of thiobenzamide (TB) (2.5 mg/100 g b.w.) by stomach tube to male rats, an increase of liver weight was evident within 2 days. It was associated with an increase of hepatic DNA, in the incorporation of [3H]thymidine into nuclei of both hepatocytes and bile duct cells and also in the mitotic index of both types of cells. Liver water content and morphology as well as serum GPT activity were unchanged. In conclusion, TB administration in a single dose below the necrotic threshold stimulates multiplication of liver cells without evidence of damage
The protection of rat liver autophagic proteolysis from the age-related decline co-varies with the duration of anti-ageing food restriction
No full textRestricting caloric intake (CR) well below that of ad libitum (AL) fed animals
retards and/or delays many characteristics of ageing and the occurrence and
progression of age-associated diseases, efficacy depending on duration. The
hypothesis that the anti-ageing effect of CR might involve stimulation of the
cell-repair mechanism autophagy was tested. The effects of ageing and duration of
anti-ageing CR on liver autophagic proteolysis (AP) were explored in male AL
Sprague-Dawley rats aged 2-, 6-, 12- and 24-months; and 24-month-old rats on a CR
diet initiated at 2-, 6- and 12-month of age or initiated at age 2-months and
interrupted at age 18 months. The age-related changes in the regulation of AP
were studied by monitoring the rate of valine release in the incubation medium
from isolated liver cells by an HPLC procedure. Results show that the maximum
attainable rate and the regulation of AP decline with increasing age; that
changes are prevented by anti-ageing CR initiated at young age, that the
protective effects of CR change with the duration of diet. It is concluded that
the data are compatible with the hypothesis that AP and improved membrane
maintenance might be involved in the antiageing mechanism of CR
EFFECTS OF ANTILIPOLYTIC AGENTS ON RAT-LIVER PEROXISOMES AND PEROXISOMAL OXIDATIVE ACTIVITIES
Full text linkTHE ENDOCRINE CONTROL OF PEROXISOME FUNCTION - EFFECTS OF ANTILIPOLYTIC AGENTS ON RAT LIVER PEROXISOMES
No full textMitochondrial myopathy in rats fed with a diet containing beta-guanidine propionic acid, an inhibitor of creatine entry in muscle cells.
Full text linkIn rats with phosphoryl-creatine depletion (fed a standard Randoin-Causeret diet
containing 1% beta-guanidine propionic acid) abnormal mitochondria were observed
in slow skeletal muscles, often containing paracrystalline inclusions very like
those induced by ischaemia or mitochondrial poisons and in human mitochondrial
myopathy
The age-related accumulation of dolichol in rat liver may be correlated negatively with expectation of life
No full textIn order to test the hypothesis that the ageing-related alteration in membrane
lipids might reflect the biological age of rodents, the levels of liver dolichol
were assayed by the HPLC procedure in male ad-libitum fed (AL) Sprague-Dawley
rats aged 2, 6, 12 and 24 months, and in 24-month-old rats on anti-aging
food-restrictions (FR) differing in duration and in their effects on longevity.
Results showed that the effects on liver dolichol of FR initiated at 2, 6 and 12
months of age, or initiated at 2 and interrupted at 18 months of age were
significantly different, and reflected the differences in the effects of FR on
expectation of life (the longer the expected residual lifespan the lower the
content in liver dolichol). The conclusion is that assay of the quantity of
dolichol in the liver tissue may be used as a marker of the biological age of the
animal and therefore as an important biomarker of ageing
Benefical effects of the oral administration of vanadyl sulphate on glucose metabolism in senescent rats
No full textWe investigated the effects of the oral administration of vanadyl sulphate (0.5
mg/ml in the drinking water) on glucose homeostasis of 3-month- and 24-month-old
rats. Results show that aging is associated with alteration of the oral glucose
tolerance test and impairment of the postprandial accumulation of glycogen in
skeletal muscles and that the oral administration of vanadyl sulphate rapidly
normalizes the inbalance of glucose metabolism in senescent rats. It is suggested
that vanadate administration may restore the ability of skeletal muscles of
senescent rats to respond to circulating insulin efficiently
HEPATIC PROTEIN-DEGRADATION AFTER ADMINISTRATION OF ANTILIPOLYTIC AGENTS - A MODEL FOR STUDYING LIVER AUTOPHAGY
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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