Acta Medica Okayama volume39 issue6

Glial fibrillary acidic protein (GFAP) was purified from human spinal cord and cerebral white matter. GFAP was localized by an immuno-peroxidase method in normal adult and fetal human brains, rat brains, and 152 central nervous system (CNS) tumors. GFAP was found in reactive and normal astrocytes, immature cells of fetal brain at the 18th to 21st gestational weeks, and normal rat astrocytes. This GFAP staining was quite specific for glial tumors, including astrocytomas, glioblastomas, astroblastomas, and ependymomas. GFAP-positive cells were also found in oligodendrogliomas and choroid plexus papillomas, and they were interpreted as being astroglial or ependymal differentiations. Stromal cells in cerebellar hemangioblastomas were negative. However, engulfed astrocytes were found at the periphery of such tumors and often adjacent to the proliferate blood vessels. In meningiomas, neurinomas, metastatic carcinomas, pituitary adenomas and other non-glial tumors, GFAP-positive cells were not identified.

An autopsy case of hypertrophic cardiomyopathy showing clinical features of dilated cardiomyopathy was reported. The patient was a 60-year-old female complaining of chest discomfort from the age of 40. At autopsy, both ventricles were dilated. Microscopically myocardial loss, fibrosis and disarray of hypertrophic myocardial fibers were observed. The areas showing myocardial disarray were distributed close to the scar-like fibrotic areas. Coronary arteries and intramyocardial arterioles showed minimal stenotic changes.

Free amino acid contents in various guinea pig tissues were determined with an amino acid analyzer. The most abundant amino acids in these tissues were: Gly and Glu in the liver and kidney, Gln, Glu and Ala in the heart, Glu and Gln in the brain, Gly in the blood plasma and Lys in erythrocytes. Glutathione was present as the reduced form in these tissues. Cystine was not detected except in the blood plasma, but cysteine was present in these tissues. These results indicate that most thiols are present in the reduced form in these guinea pig tissues. Taurine contents were low compared with those in rat tissues. The results were discussed in relation to the metabolism of sulfur-containing amino acids, and it was suggested that the oxidative metabolism of L-cysteine was lower in guinea pig tissues than in rat tissues.

Age-related alterations in the host defense system have been vigorously investigated because of increased susceptibility to infection and neoplasms in the aged. Although monocyte-macrophages form a major part of the cellular defense against microorganisms, the majority of investigations has been limited to neutrophils and lymphocytes. The present study, designed to determine the influence of age on mononuclear phagocytes, revealed no significant decrease in the absolute number of blood monocytes, but did reveal a tendency for the chemiluminescence of blood monocytes to decrease (p less than 0.10) and a significant decrease in the numbers of macrophage precursors (p less than 0.05) in the aged (over 70 year old), in comparison with controls (under 40 years old). On the basis of these findings, functional alterations of monocyte-macrophages seem to participate in the increased susceptibility to infection in the aged.

Basophil histamine release induced by allergens (house dust and Candida albicans) and anti-IgE was examined in 31 patients with bronchial asthma in relation to patient age, age at onset of the disease and serum IgE levels. Basophils from patients under 40 years of age generally released a significantly large amount of histamine by stimulation with house dust and anti-IgE. On the other hand, histamine release from patients over 41 years of age was generally not marked when the cells were incubated with house dust and anti-IgE, although, in some cases, the release induced by C. albicans was fairly marked. Basophils from patients under 30 years of age at onset were reactive to house dust and anti-IgE, while the cells from patients over 41 years of age at onset tended to be reactive only to C. albicans. Basophils from patients with low serum IgE levels were less reactive than the cells from patients with high levels of IgE to house dust and anti-IgE. C. albicans-induced release of histamine did not correlate with serum IgE levels.

The appearance of epileptiform discharges in electrocorticograms was induced by a unilateral injection of CoCl2 solution into the sensorimotor cortex of rats. Accumulation of cyclic AMP elicited by ouabain or a high concentration of potassium ions was determined in slices from different cortical areas of rats 9 or 10 days after the injection. In the anterior cortex, the depolarization-elicited accumulation of cyclic AMP was significantly higher in the cortical area ipsilateral to the injection site than in the contralateral cortical area. In the posterior cortex, a similar but not significant difference in the accumulation of cyclic AMP was noted.

The effects of caerulein on gastric motility in urethane-anesthetized rats were studied. Caerulein administered into the lateral cerebral ventricle (i.c.v.) and jugular vein (i.v.) caused predominantly an inhibitory effect on gastric motility but sometimes an excitatory or a biphasic effect. The inhibitory response was reduced after vagotomy and/or splanchnicotomy, or after guanethidine. The remaining inhibitory response was abolished by tetrodotoxin, but was resistant to atropine and guanethidine. The excitatory response was abolished by atropine. Discharges of the gastric branch of the vagus nerve were decreased by i.v. injection of caerulein but increased by i.c.v. injection, whereas those of the splanchnic nerve were increased by both i.v. and i.c.v. injection. These results suggest that caerulein causes an inhibition of gastric motility by centrally stimulating vagal non-adrenergic inhibitory nerves and splanchnic adrenergic nerves and inhibiting vagal cholinergic nerves, and by peripherally stimulating non-adrenergic inhibitory neurons of the myenteric plexus. This peptide causes an excitation by stimulating cholinergic neurons of the myenteric plexus.

Vecuronium is hydrolyzed in the body to 3-deacetyl (ORG 7268), 17-deacetyl (ORG NC58), and 3, 17-bis-deacetyl (ORG 7402) derivatives. Interactions of vecuronium and these metabolites were studied in phrenic nerve-hemidiaphragm preparations of rats. As already reported, ORG 7268 had a potent neuromuscular blocking action, and ORG NC58 and ORG 7402 had a weak neuromuscular blocking action. As expected, ORG 7268 increased the degree of neuromuscular block by vecuronium. However, a low concentration (10 microM) of ORG NC58 and ORG 7402 reversed the block by vecuronium. At a high concentration (50 microM), ORG NC58 and ORG 7402 increased the degree of block by vecuronium. Although we do not have enough data to explain these paradoxical reversal of neuromuscular block at this moment, we postulate that these results reflect the interaction between "slow" and "fast" competitive antagonists. Regardless of the mechanism, it should be emphasized that the concentrations of ORG NC58 and ORG 7402 which are necessary to reverse the block are much lower than those which facilitate the block. It is conceivable that this paradoxical reversal of the block occurs in experimental and clinical situations. Therefore, in determining the neuromuscular blocking action of a compound, the "antagonistic" effect of its metabolites should also be considered.

The effects of morphine on the hypothalamic corticotropin-releasing factor (CRF), norepinephrine (NE) and dopamine (DA) concentrations were investigated in non-stressed and stressed rats. Acutely administered morphine stimulated both the synthesis and release of CRF in the hypothalamus, thereby activating the pituitary-adrenocortical system in non-stressed rats, but inhibited the stress-induced CRF synthesis and ACTH-corticosterone secretion. Either a morphine or ether-laparotomy stress reduced NE and DA concentrations in the hypothalamus. A pretreatment with morphine inhibited the stress-induced reduction in the hypothalamic NE and DA concentrations, and induced a significant increase in the DA concentration. These observations suggest that hypothalamic NE and DA are involved in morphine-induced changes in hypothalamo-pituitary-adrenocortical (HPA) activity and that endogenous opiates have a role in regulating CRF secretion by interacting with hypothalamic biogenic amines.