The effect of intracerebral ouabain administration on the composition of edema fluid isolated from cats with cold-induced brain edema

Brain edema fluid was collected from cats with a freezing lesion in the left parietal cortex by the insertion into the brain of needles containing nylon wicks and connected to polyethylene tubes. The edema fluid samples which accumulated in the polyethylene tubes were regularly analyzed for Na+ and K+ content, colloid osmotic pressure, lactate dehydrogenase and creatine phosphokinase activity, and 99mTc-albumin radioactivity; the albumin tracer being introduced intravenously at the time of cold-injury. One series of cats received an intracerebral injection of ouabain solution, the control series an intracerebral injection of saline, at 100 min after the cold-injury. The ouabain injection was followed by an increase of K+ content, LDH and CPK activities but a decrease of Na+ concentration in the edema fluid, attributable to a concentration of solutes in the edema fluid as presumably water and Na+ were shifted into the cells and hence the extracellular space was reduced.

[Vasogenic cerebral oedema. Changes in membrane ATPases. Correction by a phospholipid precursor (author's transl)]

In vasogenic cerebral oedema, there is progressive quantitative and qualitative impairment of mitochondrial ATPase and of Na/K/ATPase. This impairment, which reflects the intracellular component of cerebral oedema, would appear to be related to changes in the phospholipid environment of the cell membrane enzymes. CDP choline, a metabolic phospholipid precursor, is to a certain extent capable of correcting this disturbed activity and at the same time reduce oedema.

Histoenzymatic and permeability changes in human brain adjacent to meningioma

Cerebral specimens were removed from ten patients with meningioma. Vascular permeability was tested with sodium fluorescein and a correlative study of the oxidative and hydrolytic enzyme activity was performed. Vascular permeability change was observed in half of the specimens of cortex taken from the region of the tumor. Labeled tracer diffusion was found to be either perivascular or involved microscopic ischemic areas. Fluorescein diffusion of the edematous white matter was observed in only two specimens. Enzyme activity in walls of the blood vessels was modified in the fluorescent specimens. Alkaline phosphatase and oxidoreductase activities were decreased. Experimental results have shown a relationship between increased vascular permeability and metabolic disorder of both vascular walls and cerebral cortex. Our findings agree with Zülch's hypothesis regarding a "hemodynamic" mechanism in the formation of edema by extraneural compression.

A possible mechanism for cholesteryl ester formation during demyelination: lecithin:cholesterol acyltransferase (LCAT) activity in rat brain

Lecithin:cholesterol acyltransferase (LCAT) activity has been examined in the rat by using a brain homogenate preparation as the phospholipid substrate and blood plasma as the enzyme source. LCAT activity was detected on using 60 mul of serum onwards. Successive experiments have also shown that LCAT activity is present in the edematous rat brain tissue homogenate when incubated with inactivated rat plasma as substrate. The results are discussed in relation to cholesteryl ester accumulation in brain during demyelinating diseases.

[Glial histoenzymatic study in human cerebral edema (collateral edema in glial tumors)]

Histoenzymatic study was performed on neurosurgical specimens. Two patterns of reactive astrocytes were found. Normal shape cells with perivascular processes were observed in subcortical white matter and in moderate edematous changes. Hypertrophic cells without processes were seen in severe edematous changes. The role of glia in the selective vulnerability of the white matter is discussed.

[Proteolytic enzyme activity in the cerebrospinal fluid after head injury--a preliminary report (author's transl)]

Report on seven cases of severe head injury, where proteolytic enzyme activity in the ventricular fluid was measured within a period of eight days. The result was positive in four cases. This finding is discussed in relation to clinical features and morphology. Earlier reports and these results are considered.

Enzyme histochemistry of rat interfascicular oligodendroglia, with special reference to 5'-nucleotidase

The interfascicular oligodendroglia of the rat striatum nucleus is studied in control animals and under experimentally induced brain edemas. Enzyme histochemical studies were performed. Normal oligodendrocytes show two different enzymatic distributions. While Mg2+-ATPase, TPPase, TPPase, adenylate cyclase and SDH are shown to be situated at the cell bodies and some proximal processes, 5'-nucleotidase reaction is seen at the cell fine distal processes. In spite of its trong activity in oligodendroglial endings the latter enzyme is not seen at the myelin sheath. This sheath and the interfascicular cells being intimately related, 5'-nucleotidase appears to be important not only during myelination, as almost all authors emphasize, but also in the adult myelin metabolism. Experimental brain edema shows some changes in the interfasicular oligodendroglia enzymatic activites for 5'-nucleotidase, Mg2+-ATPase and adenylate cyclase. A progressive disappearance of the former enzyme is observed. These features and those of derived from local ionic alterations may be concerned with the special susceptibility of white matter for some types of brain swellings.

[A contribution to the pathophysiology of post-traumatic brain oedema (author's transl)]

The aim of this paper is to contrast new results obtained on the activities of lysosomal proteases in the brain of traumatized animals with the previously held opinions concerning the development of post-traumatic brain oedema. Two hours after a standardized head injury in the cat, acid and neutral proteases were determined in the brain homogenate. Total as well as free activity, especially of the neutral proteases, were markedly increased after head injury, a circumstance indicating the important role of lysosomes in the development of post-traumatic brain oedema. It is postulated that not hypoxia alone, but primary or secondary disturbance of lysosomal function is the predominant factor in the development of brain oedema. Release of enzymes -- especially proteases -- causes irreversibility of initial vascular oedema by autolysis of cellular structures.

Serum enzyme activity of hydroxybutyric dehydrogenase (HBD) and heat inactivated lactate dehydrogenase (LD) after operations on intracranial aneurysms

The relation between clinical signs of parenchymatous cell damage after brain surgery and the serum activity of the LD-isoenzymes determined either as HBD or as heat inactivated LD, has been studied in 44 patients operated upon for intracranial aneurysms. Seven patients had a postoperative increase of the serum enzyme activity above the upper normal limit. All these showed neurological symptoms as compared to only 14% of those who had a postoperative enzyme level within normal limits. This speaks strongly in favour of a relation between the brain cell damage and the increase of the serum activity of the LD-isoenzyme. Since only 15% of the patients had a pathological enzyme level, it is further suggested that an uncomplicated operation for intracranial aneurysm should not cause an increase of the HBD or heat inactivated LD above the upper normal limit.