Role Of Blood Research Articles

Neuronophagia by leukocytes in experimental spinal cord injury.

Experimental spinal cord injury was produced in cats by compression trauma. The major histologic features in the first 24 hours following injury included hemorrhagic necrosis, edema, and acute inflammation of gray and white matter. Neutrophilic leukocytes (NL) were apparent in the walls of and adjacent to veins and venules within four hours of injury, but large numbers of NL were not observed in tissue until eight to 24 hours. Acute inflammation was especially prominent in gray matter, and NL frequently surrounded and phagocytized neuronal somata. Large numbers of NL and neuronophagia by leukocytes were evident only in areas of hemorrhage. The role of blood in producing the acute inflammatory response and in generating chemotactic factors responsible for neuronophagia is incompletely understood. Neutrophilic leukocytes, in addition to their response as phagocytes, release histolytic enzymes, reactive species of oxygen, and proinflammatory factors which lead to further tissue necrosis and inflammation.

Role of Blood and Fibrinogen in Development of Intraperitoneal Adhesions in Rats

One hundred and twenty rats were divided into six groups and laparotomized. In three of the groups the cecum was left intact. In one of these groups the cecum was only lifted up through the abdominal incision and then replaced in the abdominal cavity. In another group the intact cecum was bathed with a certain amount of blood from the animal's tail. In the third group the uninjured cecum was covered with fibrinogen in an amount equivalent to that in the blood used in the other group. In the remaining three groups the cecum was traumatized in a standardized way. In one of these groups the injured cecum was left untreated. In another group the traumatized cecum was bathed in homologous blood and in the third group the injured cecum was treated with fibrinogen as described above. Two weeks later the rats were killed and the number and quality of the intra-abdominal adhesions were studied. The findings in the present investigation indicate that neither blood nor fibrinogen per se induced adhesions to the serosa. On the contrary, a defect in the serosa initiated the formation of adhesions.

Glucose utilization and role of blood in endotoxin shock.

The present study was conducted to explore influences modifying glucose uptake in canine blood administered LD100 E. coli endotoxin. Particular emphasis was given to assay the role of the white blood cell (WBC) in glucose utilization. Significant increases in glucose uptake and lactic acid production, attributed to increased activity of the WBC, were observed 1-3 h after endotoxin was added to blood in vitro. Although a net increase in glucose utilization was noted, endotoxin simultaneously exerted adverse effects by depressing glucose uptake below predicted values (Q10 = 2.12 with LD100 endotoxin vs. 2.78 in saline controls) and increasing WBC mortality rate. Blood from dogs pretreated with sublethal doses of endotoxin in vivo utilized glucose at an accelerated rate when subjected to endotoxin in vitro. Excess glucose was consumed because of elevated numbers of white blood cells although additional glucose requirements after endotoxin were independent of temperature between the ranges of 34-41 degrees C. All animals pretreated with daily sublethal injections of endotoxin for 3 days survived superlethal doses of endotoxin.

The Role of Blood and Platelets in Atherosclerosis and the Complications of Atherosclerosis

There appear to be at least three ways in which the blood, and particularly the platelets, may contribute to the development of atherosclerosis and its complications: 1. In the mechanism causing endothelial injury and the response of the smooth muscle cells to vessel injury. 2. Through the formation of persistent mural thrombi which are organized into intimal thickenings. 3. Through the formation of thrombi in association with advanced atherosclerosis that may be either (a) mural thrombi which fragment and shower the distal circulation with platelet emboli or (b) occlusive thrombi.

On the role of blood and muscle cholinesterases in the hydrolysis of subecholine and acetylcholine in the cat

Summary In the cat, when all cholinesterase activity of blood and tissues is completely and irreversibly inhibited by armine, the neuromuscular blocking dose of subecholine is reduced 100-fold (from 0.54 to 0.0054 micromoles/kg i.v.) and the blocking dose of ACh is reduced 460-fold (from 37 to 0.08 micromoles/kg). If the blood cholinesterases are completely inhibited, while the cholinesterase activity of the muscle remains unimpaired, the blocking doses of subecholine and ACh are reduced only about 2-fold. In the experiments, where strong or complete inhibition of muscle cholinesterases without significant inhibition of blood enzymes was achieved, the potentiation of blocking potency was as great as 100-fold for subecholine and 250-fold for ACh. One can suppose that in the cat the hydrolysis of intravenously injected ACh and subecholine occurs mainly in the tissues (in muscles and, probably, in other tissues too), and the hydrolysis in blood plays a much less important role.

In vitro metabolism of androgens in whole human blood.

ABSTRACT Radioactive dehydroepiandrosterone, testosterone, androstenedione, 5-androstene-3β,17β-diol, and 4-androstene-3β,17β-diol have been incubated with whole blood obtained from normal males and females and from subjects with idiopathic hirsutism. The results show that transformations and interconversions of androgens can take place in whole blood and of particular interest is the transformation of the less to the more biologically active androgens. The implications of these transformations and interconversions in the possible role of blood in the control of endocrine homoeostasis is discussed.

Hormonal regulation of rat kidney transamidinase; effect of growth hormone in the hypophysectomized rat.

Transamidinase activities have been demonstrated to be markedly lower in kidneys from hypophysectomized rats, than in kidneys from intact or sham-hypophysectomized rats. Adrenalectomy, thyroidectomy, or castration of the male rat is without any effect on the enzyme activity. Hypophysectomized rats given 3 daily doses of small amounts of growth hormone have greater kidney transamidinase activities than untreated hypophysectomized rats. The administration of a number of other hormones is without any effect on the enzyme activity. The use of the enzyme assay as a sensitive and specific measurement of growth hormone activity is suggested. The role of blood and kidney creatine and food deprivation in the alteration of kidney transamidinase activities was investigated. The loss of enzyme activity in the first 3 days following hypophysectomy can be attributed to food deprivation and the high levels of blood and kidney creatine. Food consumption and blood and kidney creatine of the hypophysectomized rats returned...

The Role of Blood in Disaster

The Role of Blood in Disaster

On the Role of Blood in Ovulation in Aëdes aegypti, Linn

The intimate association between a blood meal and ovulation in all female mosquitos, with the exception of a few (de Buck, Roubaud) has been clearly recognised; but the peculiar manner in which the presence of blood in the stomach can influence the formation of eggs is not understood. Two explanations may be suggested: it may either act as a physico-chemical stimulus to the ovarian follicles, or certain constituents in the blood may furnish some nutrient material for the development of the eggs.