摘要:

Specific in vitro glucocorticoid uptake and binding activity of spleen and splenic leukocytes were examined in adult (2- to 3-month-old) and senescent (24- to 28-month-old) male, adrenalectomized Sprague-Dawley and Wistar rats. No significant differences in these parameters were evident between young and old animals of either strain. Moreover, cortisol inhibition of [5-3H]-uridine uptake and the total number of glucocorticoid binding sites of spleen and its leukocytes were found to be similar in these two age groups. It was concluded that age has no effect on the glucocorticoid responsiveness of the splenic tissues of the two strains of male rats studied.

ISSN:0304-324X    

DOI:10.1159/000212516

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Carbohydrate and lipid substrate changes associated with fasting were similar in aged (over 24 months), 1 -year-old and young (about 4 months old) rats. In all three age-groups fasting reduced liver and skeletal muscle glycogen, elevated myocardial glycogen and plasma free fatty acid (FFA) levels, but did not significantly affect blood glucose. With refeeding, the myocardium from aged and 1-year-old rats lacked the glycogenesis observed in young rats. Less glycogenesis was also observed in aged soleus muscles during refeeding than in soleus muscles from young or 1 -year-old rats. This depressed glycogenesis in the old rats could not be attributed to any change in the tissue triglyceride or plasma FFA response to refeeding, but was accompanied by a slightly greater elevation of glucagon in the aged rats. Though its etiology is unclear, the depressed glycogenesis indicates that aging affects aspects of carbohydrate metabolism in addition to the known decrease in glucose tolerance.

ISSN:0304-324X    

DOI:10.1159/000212517

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Plasma choline concentrations and both plasma and erythrocyte cholinesterase activities were measured in young and old Fischer 344 and Sprague-Dawley rats. Plasma choline concentration and erythrocyte cholinesterase activities do not change with age in either the Fischer 344 or Sprague-Dawley rats. There is a marked age-related increase in plasma cholinesterase activity in the Fischer 344 rats, however.

ISSN:0304-324X    

DOI:10.1159/000212518

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The superoxide dismutase (SOD) activities in cerebral cortex of rat during aging are reported. The specific activity of cytosol SOD (Cu/Zn dismutase) decreases progressively from the 1st to the 30th month of postnatal life, whereas the specific activity of mitochondrial SOD increases with age. The alterations in the two enzymatic forms of SOD in the cerebral cortex of rat during aging may be due to separate regulation mechanisms.

ISSN:0304-324X    

DOI:10.1159/000212519

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

We have studied the ability of N-methyl-N′-nitrosourea to induce pancreatic carcinoma within 5 months when single doses were administered to C57BL/6J male mice at 3, 12 and 24 months of age. Pancreatic tumors were not observed in the young and middle-aged animals, but 3/15 of the surviving aged mice showed gross evidence of carcinoma. Ultrastructural analysis revealed in each tumor the presence of two populations of undifferentiated cells, both cell types possibly being of acinar cell origin. The observation of pancreatic carcinoma only in aged animals treated with an environmental carcinogen may be a model paralleling the human condition, which also shows a strong age dependenc

ISSN:0304-324X    

DOI:10.1159/000212520

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The action of ginseng saponins on cell numbers, glucose uptake and lactate production and the activities of specific enzymes associated with glucose oxidation, was tested using a human diploid fibroblast strain. No augmentation of cell numbers was observed. There was a significant increase in the level of cellular lactate levels and in the specific activities of enzymes associated with an anaerobic shift in metabolism. The possible relationship between these findings and the reputed efficacy of ginseng administration in the elderly is discussed.

ISSN:0304-324X    

DOI:10.1159/000212521

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The relationship of the serum iron-binding capacity (IBC) to the serum proteins and other haematological parameters was studied in 96 elderly subjects. With two exceptions, IBC levels above the normal range were confined to cases of anaemia with transferrin saturation levels of less than 12%. In 13 cases the IBC was below normal, and in 9 it was normal in the presence of iron deficiency; in these groups the IBC correlated with serum albumin, and there was a clinical explanation for protein depletion. In cases with normal serum albumin and normal transferrin saturation, there was no decline in IBC with age. The best serological index of iron status was the transferrin saturation, which was less than 12% in significant iron deficiency. Malabsorption of inorganic iron was demonstrated in 11 out of 30 iron-deficient patients, 4 of whom had reduced IBC, but there was no relationship between iron absorption and the IBC.

ISSN:0304-324X    

DOI:10.1159/000212522

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Human ageing is most usefully conceptualised as an interaction between intrinsic and extrinsic processes. Comparison of age-associated trends in populations living under different environmental conditions provides a method of recognising the effects of extrinsic influences. This paper compares the age-associated trend in mean frontal plane QRS axis in the male adult population of Pukapuka with the trend observed in an age-matched sample from a British population. The Pukapukans show no rise in mean blood pressure with age and have other features placing them at low risk of coronary heart disease. Although the British population showed the shift to the left in mean QRS axis characteristic of economically advanced populations there was no change in mean QRS axis with age among the Pukapukans. The conclusion is drawn that the shift with age in QRS axis observed in advanced populations is extrinsic in origin but is not necessarily a manifestation of coronary heart disease.

ISSN:0304-324X    

DOI:10.1159/000212523

出版商:S. Karger AG    

年代:1982

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212524

出版商:S. Karger AG    

年代:1982

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212525

出版商:S. Karger AG    

年代:1982

数据来源: Karger