The vasculature of experimental brain tumours. Part 3. Permeability studies.

The aim of this work was to elucidate the direction and time-course of transport processes which may affect the accumulation of oedema associated with experimental brain tumours. Astrocytomas were produced in BD-IX rats by intracerebral injection of cultured neoplastic glial cells. The cell line used was cloned from a culture of a primary mixed glioma induced by transplacental administration of N-ethyl-N-nitrosourea (ENU).

Development of intraductal protein plugs in rats fed with ethanol for 18 months.

The pancreatic tissue damage was investigated histologically in rats kept on liquid diet containing 6% ethanol for 18 months. Rats kept on a liquid diet without ethanol served as controls. The daily ethanol intake was 1.

Ranitidine inhibits the trophic effect of caerulein on the pancreas in rats (preliminary data).

The aim of this study was to establish whether ranitidine treatment influences the trophic effect of caerulein on the pancreas of rats. Ranitidine (20 mg/kg b.w.

Comparative histochemical and immunofluorescent observations in thiamine deficient encephalopathies.

Histochemical and immunohistological examinations were carried out at different stages of thiamine-deficient encephalopathy in rats. The respiratory enzymatic activity decreased in the most damaged area correlating well with the neuropathological findings. There was an inverse relationship between the damaged area and its marginal zone; the latter showed an increase of the same enzymatic activity.

Symmetric central thalamic necrosis in experimental thiamine deficient encephalopathy.

Besides the classical lesions, symmetric necrosis was found in the thalamus of pyrithiamine treated rats. The barrier systems of the two areas differ already in healthy animals and behave differently during the illness.

Incorporation of 3H-2,3-DL-valine into pancreatic proteins of adrenalectomized rats stimulated with pancreozymin-CCK and secretin.

Incorporation of labelled valine was investigated in bilaterally adrenalectomized rats stimulated with pancreozymin-CCK and secretin 14 days after operation. The growth of rats, the blood pressure, the amount of pancreatic juice and the amylase output was less in the adrenalectomized animals as compared with sham operated or adrenalectomized and corticosterone substituted controls. The amylase concentration in the pancreatic juice reveals no difference between the groups but the output of amylase remained below that of the controls.

Exit routes for secretory proteins from the dog pancreas.

Unlabelled: The relative importance of the pancreatic venous and lymphatic routes for the transport of enzymes away from the pancreas was investigated. The activities of lipase and amylase were compared in arterial plasma, pancreaticoduodenal lymph and venous plasma, pancreatic interstitial fluid and juice in 31 anaesthetized dogs. Enzyme activities were determined before, during and after stimulation of the acinar parenchyma by 4 U/kg b.

The hepatic tissue spaces.

In a controlled study concerned with the site of intrahepatic lymph formation, liver tissue from normal dogs, cats, rats and from cats with ligated hepatic lymph vessels, was subjected to light and electron microscopy. It was found that the periportal space named after Mall by whom it had been described, represents an interstitial gap of submicroscopic size. It is bordered on the one side by the hepatocytes of the limiting plate and on the other by the connective tissue fibres and processes of the connective tissue cells of the portal canal.

In acute pancreatitis the decrease of villous activity, the damage of the intestinal mucosa might be induced by agents produced during pancreatitis or by trypsin.

If injected into the blood circulation, pancreatitic abdominal exudate significantly reduces villous activity and blood pressure. A relationship can be established between the log of the exudate doses and their effects.

Absorption of pancreatic lipase from the duodenum into lymphatics.

A significantly higher lipase activity was measured in the duodenal lymph samples of 15 dogs than in each of corresponding arterial blood plasma samples collected prior to, during and after maximal hormonal stimulation of pancreatic secretion. The result may be evaluated as a sign of pancreatic lipase absorption by the duodenum into lymphatics.