摘要:

Comparative studies of the chemistry and metabolism of human and bovine arterial and venous tissue had the following results (values for bovine tissue in parenthesis): 1. In arterial tissue the contents of collagen were 21% (37%) and of elastin 20% (31%) referred to the dry weight. In veins collagen amounted to 47% (30%) and elastin to 7% (18%). The mucopolysaccharide concentration was higher in arterial (1.2 and 1.5 resp.) than in venous tissue (0.4 and 0.2% resp.). Hyaluronate, chondroitin 6-sulphate (chondroitin 4-sulphate), dermatan sulphate and heparan sulphate were identified. In arterial tissue chondroitin sulphate was predominant with 59 % and 49 % resp. In human venous tissue the main component was dermatan sulphate (65%), in bovine veins it was hyaluronate (75%). No dermatan sulphate was found in bovine venous tissue. The number of cells was higher in arteries (4.5 × 107 nuclei/g w. wt.) than in veins (2.8 × 107). 2. On in vitro incubation bovine arterial tissue metabolized 73 %, venous tissue 32% of the added [U-I4C] glucose within 12 h. In this period 2.8 and 2.4 mg lactate resp./g wet tissue were formed by arteries and veins. The specific radioactivity of lactate synthesized in arterial tissue reached that of the added [U-I4C] glucose whereas lactate formed by veins had only 36 % of the specific activity of the [U-I4C] glucose. The specific radioactivity of the acid mucopolysaccharides was 5–6 times higher in venous tissue than in arterial tissue. After labelling with 35S-sulphate a 3-fold higher specific radioactivity of venous sulphated mucopolysaccharides was observed. 3. After incubation of bovine venous tissue in the presence of I4C-acetate the specific radioactivity of phospholipids was 45 % higher than that of arterial tissue in contrast to a 50 % lower labelling of cholesterol in venous tis

ISSN:1018-1172    

DOI:10.1159/000157847

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Response of renal blood flow to regional sympathetic nerve stimulation has been studied in anesthetized cats. When the sympathetic nerves to the kidney are stimulated at frequencies within the ‘physiological range’, renal blood flow first decreases markedly and then increases over the next 3 to 5 min to a value slightly below the control level. A similar ‘escape’ of the resistance response is found when the renal nerves are stimulated under conditions of constant flow. If the frequency of renal nerve stimulation is gradually increased the onset of the escape is greatly delayed, indicating that failure of impulse transmission or severe depletion of transmitter is unlikely to be the cause of the escape phenomenon. Intraarterial infusion of noradrenaline produces increased flow resistance with little or no subsequent escape showing that the escape cannot be attributed to loss of responsiveness of the vascular smooth muscle to the adrenergic transmitter. A quantitative decrease in the amount of transmitter released per impulse and intrarenal vascular control mechanisms related to blood flow autoregulation are discussed as possible causes of the escape phe

ISSN:1018-1172    

DOI:10.1159/000157848

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

An important relationship exists between abnormalities of serum lipoproteins and atherosclerosis. A simple and reproducible system for a semiquantitative serum lipoprotein analysis is described and the determinations are sufficiently accurate for clinical use. The method is adaptable for laboratories without an ultracentrifuge and does not require elaborate equipment. The quantitative determination of serum lipoproteins complements serum cholesterol and serum triglycerides in evaluation of lipid abnormalities. The method can be used to study subtle abnormalities in ‘normal’ individuals as well as changes occurring in various disease sta

ISSN:1018-1172    

DOI:10.1159/000157849

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

The blood fibrinolytic activity was studied in 93 volunteers belonging to 3 different racial groups and related to their body weight adjusted to the ‘weight-for-height’ standard. No difference was found in this activity when overweight, underweight and standard weight British and Asian males were compared. Increased blood fibrinolytic activity was observed in overweight African Negroes as compared to those of standard weight, and decreased blood fibrinolytic activity was discovered in underweight British women when compared to those of standard weight or overweight. It is suggested that the increased fibrinolytic activity in overweight African males may be due to their increased muscular bulk, since muscles are a potent contributor of plasminogen activator to the circulat

ISSN:1018-1172    

DOI:10.1159/000157850

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

The authors produced 20% third-grade burns in rats. One, three and five days after, the animals were killed by decapitation and their cerebella examined by fluorescent and electron microscopic methods. It was observed studying both trypan blue and thorotrast techniques that the permeability of the blood-brain barrier was considerably enhanced even 5 days after burning of the skin. The opening of the so-called ‘tight-junctions’ between the endothelial cells could be observed. The possibility of the release of a vasoactive substance originating in the damaged tissues is discussed. This substance may be responsible for maintaining the longer period of increased permeability of brain capillar

ISSN:1018-1172    

DOI:10.1159/000157851

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Scanning electron microscopy of the rabbit thoracic aorta following staining with silver nitrate showed endothelial cell borders to be marked by zigzag lines outlining individual endothelial cells as oblong rhombic fields oriented with the long axis parallel to the aortic axis. The layer of endothelial cells coated an underlying layer of coarse longitudinal folds, probably foldings of the underlying elastic membranes. The individual endothelial cells were inconspicuous in uncoated specimens. Double coating with coal and gold revealed a grainy porous mass in the silver lines and a flat surface of endothelial cells studded with small round elevations. Comparative studies with transmission light microscopy and transmission electron microscopy indicated silver deposits in the endothelial cell boundaries. Fine dustlike silver sediments were also observed on the surface of endothelial cells and in the layers next to the intima.

ISSN:1018-1172    

DOI:10.1159/000157852

出版商:S. Karger AG    

年代:1970

数据来源: Karger

摘要:

Repeated treatment with large doses of vasodilators elicited small arterial changes in rats. Similar lesions developed on alternate dosage of vasodilator and vasoconstrictor preparations. The mechanical strain imposed on the vessel wall by both types of vasoactive substances is believed to play a role in the pathomechanism of the vascular changes which seem essentially to arise from the impairment of the smooth muscle cells overburdened by forced movements of the vessel wall.

ISSN:1018-1172    

DOI:10.1159/000157853

出版商:S. Karger AG    

年代:1970

数据来源: Karger

ISSN:1018-1172    

DOI:10.1159/000157854

出版商:S. Karger AG    

年代:1970

数据来源: Karger

ISSN:1018-1172    

DOI:10.1159/000157855

出版商:S. Karger AG    

年代:1970

数据来源: Karger

ISSN:1018-1172    

DOI:10.1159/000157846

出版商:S. Karger AG    

年代:1970

数据来源: Karger