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The alkaline phosphatase and DNA-RNA activities in the retinas of young and old albino mice were determined histochemically after photic exposure. Different patterns between the two age groups were obtained for the alkaline phosphatase reaction before and after photic exposure. In the young animals, more retinal layers showed increased activity after exposure whereas in the old animals, the converse was true. DNA-RNA reaction revealed decreased DNA activities in the old animals 30 h after exposure. The results were also correlated with biochemical studies on the uptake of 2-deoxyglucose, dopamine and leucine.

The development of total monoamine oxidase (MAO) and MAO-A and MAO-B in the forebrain, brainstem, cerebellum and liver of methadone-treated and normal rats were monitored with tryptamine, serotonin and benzylamine, respectively. Daily administration of methadone (10 mg/kg, s.c.) to pregnant and nursing rats substantially retarded the development of total and the A-form of MAO in the brain regions of pups but had no effect on that of MAO-B. The effect of methadone on the development of total MAO and MAO-A in the liver was only transient and less significant. This finding indicates that the perinatal opiate syndrome associated with maternal exposure to methadone is caused by the inhibition in MAO-A development in monoaminergic neurons in the brain.

The phagocytic ability of the pigment epithelium after optic nerve sectioning and tectal removal was investigated in the goldfish by the method of ingestion of latex beads. 4 days after sectioning, an increase in latex beads was evident which decreased by the end of the first week. Tectal removal also triggered increase intake of latex beads which was presented after 7 days.

The postnatal changes in the levels of radioimmunoassayable enkephalin and beta-endorphin, as well as the densities of [3H]methionine-enkephalin and [3H]naloxone binding sites in rat cerebellum, brainstem and whole forebrain were determined. The opiate peptides and the opiate binding sites reached their highest levels at the first week postpartum in the cerebellum, at the second week in the brainstem and at the third week in the whole forebrain. This finding is in line with the developmental profiles of other well-established neuronal pathways which also showed a caudal-to-rostral sequence of development. Moreover, there was a close relationship between the elevation and decline in the amounts of opiate binding sites and in the levels of opiate peptides in each brain region. These observations are consistent with other evidence which suggests that enkephalin and beta-endorphin are functioning as neurotransmitters or neuromodulators in the central nervous system.

The development of opiate receptors in whole forebrain, brain stem and cerebellum of developing rats was measured by specific [3H]methionine-enkephalin ([3H]Met-Enk) and [3H]naloxone binding. The level of opiate receptor as determined by the binding of these two opiates varied with brain region as well as with age; however, the amount of [3H]naloxone bound in the same brain region obtained from animals of the same age was greater than that of [3H]Met-Enk. Kinetic analyses of these two opiate binding sites in newborns of the same age revealed that they differed in their apparent affinities and receptor numbers. Moreover, both morphine and naloxone were equally active in competing for [3H]Met-Enk binding in all 3 brain regions during the first month after birth, whereas methionine-enkephalin was only about 30-50% as active as morphine n competing for [3H]naloxone binding in that period. These results suggest that in the rat brain there are two types of opiate receptors and that the heterogeneity of opiate receptors is already apparent during early postnatal life.

Malignant fibrous histiocytoma is a primitive mesenchymal tumor usually found in the soft tissues of the extremity or torso of adults. Only two previous reports of this lesion in the abdominal viscera are present in the world medical literature. A case is reported of three synchronous tumors in the rectum, colon, and omentum with the pathologic appearance of malignant fibrous histiocytoma. Although resected completely with a transverse colocolostomy and a low-anterior resection, the expected behavior of this tumor is one of aggressive local recurrence followed by distant metastasis. The clinical and pathologic characteristics of malignant fibrous histiocytoma are reviewed.

Solubilized Ehrlich cell plasma membrane proteins were incorporated into lipid vesicles in the presence of added phospholipid, using Sephadex G-50 chromatography combined with a freeze-thaw step. Liposomes formed in K+ exhibited high levels of Na+-dependent, alpha-aminoisobutyric acid uptake which was electrogenic and inhibited by other amino acids. The transport activity reconstituted was similar to that observed in native plasma membrane vesicles. In addition to transport by system A, leucine exchange activity (system L), Na+-dependent serine exchange activity (system ASC), and stereospecific glucose transport activity were also reconstituted. The latter was inhibited by D-glucose, D-galactose, cytochalasin B, and mercuric chloride. The medium used for reconstitution was critical for the recovery of Na+-dependent amino acid transport. The use of Na+ in the reconstitution procedure led to formation of liposomes which displayed little Na+-dependent and gradient-stimulated amino acid uptake. In contrast, all transport activities studied were efficiently reconstituted in K+ medium.

The maturation of the albino mouse visual system was studied using mainly the retinae and visual cortices. Increased proportion of ganglion cells was detected in the central region of the retinae of 4 month old animals. The relative thickness of layer 4 of the visual cortex also reached a high in the 4 month old mouse. These results were further strengthened by detection of an increase in the spicules on the dendrites of stellate cells in layer 4 of the cortex concomitant with an increase in GABA and Noradrenaline uptake in the visual cortex. All that appeared to point to that the visual system of the albino mouse reached maturation when they were 4 months old.

A specific, sensitive and reproducible radioimmunoassay is described for measurement of somatostatin in brain tissue. The sensitivity of the assay is 10 pg/tube and recovery of synthetic somatostatin added to brain homogenates was 95.8 +/- 6.2%. Dilution of tissue extracts from various brain regions showed parallelism in standard curves with labelled somatostatin. Somatostatin is shown to be widespread in the central nervous system with highest concentrations in hypothalamus, particularly the median eminence. Subcellular preparations of medial basal hypothalamus, preoptic area and amygdala indicate that over 70% of somatostatin immunoreactivity is localized to the synaptosome fraction. Recovery of activity in the P2 pellet prior to separation on sucrose gradient is approximately 100%. It is hypothesized that somatostatin, in addition to being released into blood vessels of the median eminence, may also be liberated from nerve terminals in other brain regions.

Noradrenaline, isoproterenol, adrenaline or clonidine stimulate cyclic AMP formation in human cerebellar cortex 15-20 fold and serotonin or dopamine 3-fold. The increase by noradrenaline or clonidine is dose-dependent. Propranolol completely blocks the increase induced by noradrenaline or isoproterenol but not that by clonidine. Phentolamine was ineffective in blocking cyclic AMP formation induced by noradrenaline, isoproterenol, adrenaline or clonidine. Chlorpromazine completely blocked the increase induced by noradrenaline, isoproterenol, clonidine, serotonin or dopamine.

The development profiles of [3H]methionine-enkephalin ([3H]Met-enk) binding sites and radioimmunoassayable (RIA) beta-endorphin in regions of rat brain were determined. The amount [3H]Met-enk bound reached its maximum in the 1st week after birth in the cerebellum, in the brainstem at the 2nd week, and in the whole forebrain at the 3rd week, that of RIA beta-endorphin reached its highest level at day 2 postpartum (p.p.) in the cerebellum. at days 7-15 p.p. in the whole forebrain, and at days 17-21 p.p. in the brainstem. These findings suggest that both the development of RIA beta-endorphin and [3H]met-enk sites in rat brain follow a caudal to rostral sequence. Also, the close interrelationship between the elevation and decline in the amount of [3H]Met-enk bound and RIA beta-endorphin levels in each brain region suggests that these two components are important entities of the central nervous system.

In human cerebral cortex slices noradrenaline, isoproterenol (a beta-adrenergic agonist), dopamine, apomorphine (a dopaminergic agonist), and serotonin stimulated cyclic AMP formation: noradrenaline greater than or equal to isoproterenol greater than dopamine = apomorphine = serotonin. Clonidine (and alpha-adrenergic agonist) was ineffective in stimulating cyclic AMP formation in temporal cortex slices. The stimulatory effect of noradrenaline and isoproterenol was blocked by propranolol (a beta-adrenergic blocker) but not by phentolamine (an alpha-adrenergic blocker). Pimozide (a selective dopaminergic antagonist) inhibited the increase of cyclic AMP formation induced by dopamine or apomorphine but not that induced by noradrenaline, isoproterenol, or serotonin. Neither propranolol or phentolamine had any effect on dopamine- or serotonin-stimulated cyclic AMP formation. Chlorpromazine blocked the increase of cyclic AMP formation induced by noradrenaline, dopamine or serotonin, while cyproheptadine, a putative central serotonergic antagonist, was ineffective. These observations suggest that there may be at least two monoamine-sensitive adenylate cyclases in human cerebral cortex which have the characteristics of a beta-adrenergic and a dopaminergic receptor, respectively, and also possibly a serotonergic receptor.

The insidious presentation of intramesocolic perforation in diverticulitis has been reviewed, and two cases of intramesocolic perforation associated with pneumopylephlebitis have been reported. Review of the two previously reported cases of pneumopylephlebitis associated with diverticular perforation suggests that these may have been intramesocolic perforations as well. Exploratory laparotomy is clearly indicated in cases of pneumopylephlebitis. In patients with recurrent sepsis without a probable source, a water-soluble contrast enema is recommended. If conservative measures fail, an exploratory laparotomy should be performed to exclude intramesocolic abscess.