Polyamines induce precocious development in rats. Possible interaction with growth factors.

The study reports the effects of daily subcutaneous injections of the biogenic polyamines putrescine, spermidine and spermine (10 mg/kg each) given for a short postnatal period, on growth and development of rats. Polyamine treatment, while only slightly enhancing normal body weight gain, prevented the weight loss caused by surgical injury of 5-day-old animals. The treatment resulted in earlier eyelid and ear opening and in earlier maturation of righting and gripping responses.

A comparison of intraventricular and intraparenchymal cerebellar allografts in rat brain: evidence for normal phosphorylation of neurofilaments.

Allografts of embryonic (E14-E15) rat cerebellum in adult brain were compared using the intraparenchymal and intraventricular transplantation techniques. We studied the expression and distribution of phosphorylated neurofilament (PNF) epitopes, nonphosphorylated neurofilament (nPNF) epitopes, synapse-associated antigens, glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP). Both intraventricular and intraparenchymal grafts developed a clear trilaminar organization.

gamma-Vinyl GABA in endopiriform area suppresses kindled amygdala seizures.

Suppression of kindled amygdala seizures in rats followed bilateral infusion of the GABA transaminase inhibitor gamma-vinyl-GABA (GVG) into the endopiriform area of the forebrain. The deep prepiriform cortex of the rat is an important site for both initiation and arrest of generalized seizures induced by systemic convulsants. To determine whether this area also regulates the spread of amygdala seizures, the irreversible GABA-transaminase blocking agent, GVG (vigabatrin) was infused bilaterally in the deep prepiriform area in amygdala-kindled rats.

Alpha frequency in schizophrenia: an association with enlarged cerebral ventricles.

Low alpha frequency (less than 10.2 Hz) occurred more frequently in medication-free schizophrenic patients than in normal control subjects, as determined by quantitative EEG analysis. Furthermore, those patients with low alpha frequency had significantly larger lateral ventricles, as measured by CT scan, than did other schizophrenic patients (mean +/- SD ventricle-brain ratios = 9.

Chronic cocaine effects on peripheral biogenic amines: a long-term reduction in peripheral dopamine and phenylethylamine production.

The short- (during 12 h after last treatment) and long- (6 weeks after last treatment) term effects of repeated administration of cocaine on the total output of norepinephrine (NE) and its metabolites (sum NE), dopamine (DA) and its metabolites (sum DA) as well as the excretion of 5-hydroxyindoleacetic acid (5-HIAA) and phenylethylamine were evaluated in rats. The concentration of NE, DA and 3,4-dihydroxyphenylacetic acid (DOPAC) in the celiac ganglion after 1, 2 and 3 weeks of repeated cocaine administration were also measured. Sum NE remained unchanged during the cocaine treatment but NE and normetanephrine excretions were significantly decreased and increased respectively.

Schizophrenic dementia. Clinical and computed axial tomography correlates.

Twenty-seven chronic schizophrenic patients and nine other psychiatric patients closely matched in education were compared on the Halstead-Reitan Battery and the Wechsler Adult Intelligence Scale (WAIS). The schizophrenic patients as a group showed significantly poorer performance on the WAIS (full scale: X +/- SD, 92.9 +/- 2.

D-dopa and L-dopa similarly elevate brain dopamine and produce turning behavior in rats.

In the intact rat, intragastric administration of D-dihydroxyphenylalanine (D-DOPA) together with carbidopa (alpha-methyldopa hydrazine, a peripheral dopadecarboxylase inhibitor) increased striatal dopamine concentration to the same extent as a similar treatment with L-DOPA plus carbidopa. In rats with unilateral 6-hydroxydopamine-induced lesions of their substantia nigra, both stereoisomers of DOPA produced significant increases in dopamine and its metabolites in the intact striata. Although dopamine concentrations in the lesioned striata did not change, a significant increase in dopamine metabolites was observed, indicating some extraneuronal formation of dopamine.

Neuropeptide Y inhibits the nicotine-mediated release of catecholamines from bovine adrenal chromaffin cells.

The possible role of neuropeptide Y (NPY) in catecholamine secretion was studied by using bovine adrenal chromaffin cells. NPY produced a concentration-dependent inhibition of nicotine-stimulated norepinephrine and epinephrine release from bovine chromaffin cells with IC50 (concentration of NPY which inhibits 50% of maximum release of catecholamines) values of 1.8 x 10(-9) M and 1.

Stability of CT scan findings in schizophrenia: results of an 8 year follow-up study.

Earlier cross-sectional studies have suggested that CT findings of ventricular enlargement and increased cortical markings in schizophrenic patients are not progressive, but individual patients have rarely been followed prospectively. Fifteen patients with chronic schizophrenia were rescanned on the same model machine after 7 to 9 years of continuous illness and, in seven cases, of continuous hospitalisation. It was not possible to demonstrate significant changes in either ventricular-brain ratio or frontal atrophy scores.

Epilepsy, psychosis and schizophrenia.

A connection between epilepsy, especially temporal lobe (psychomotor, limbic) epilepsy (TLE) and schizophrenia has been proposed by a number of investigators. The evidence both supporting and challenging this widespread idea is reviewed, and several hypotheses are considered that may account for the higher incidence of this form of epilepsy and of schizophrenic psychoses after adolescence.

Schizophrenic births and viral diseases in two states.

In order to investigate a possible relationship between schizophrenic births and viral diseases, the birth month and year of all state hospital admissions for schizophrenia in Connecticut and Massachusetts from 1973-1974 were compared with the occurrence of reportable viral diseases for 1920-1955. Data was statistically examined by time series using spectral analysis. Statistically significant coherences were found between schizophrenic births and measles (both states), varicella-zoster (Connecticut) and polio (Connecticut).

Schizophrenia, just the facts. What do we know, how well do we know it?

The basic facts of schizophrenia are subjectively reviewed in terms of their reproducibility and significance for understanding the disorder. Some of the facts that are either less well known or of greater importance for future investigation are discussed in more detail. The purpose of establishing what we know about schizophrenia is to develop firm ground for generating hypotheses.

Cerebellar allografts in brain of quaking mice.

Fragments of normal embryonic cerebellum were transplanted into adult Quaking mice to examine using peroxidase-antiperoxidase immunocytochemistry the development of genetically normal tissue in an abnormal host environment. The Quaking mouse animals used as hosts are characterized by defective myelin associated glycoprotein. Normal characteristic expression and distribution of neurofilaments was observed in the cerebellar grafts.

Local autoimmune reaction and behavioral abnormalities after repeated nerve injury: an experimental study.

Sciatic nerves of rats were submitted to single and repeated injuries. The animals' gait was used to study motor function; autophagia was used to study sensory effects. An association with local post-traumatic autoimmune reaction was sought, after histochemical studies of the nerves.

Mesocortical dopaminergic function and human cognition.

In summary, we have reviewed rCBF data in humans that suggest that mesoprefrontal dopaminergic activity is involved in human cognition. In patients with Parkinson's disease and possibly in patients with schizophrenia, prefrontal physiological activation during a cognitive task that appears to depend on prefrontal neural systems correlates positively with cognitive performance on the task and with clinical signs of dopaminergic function. It may be possible in the future to examine prefrontal dopamine metabolism directly during prefrontal cognition using positron emission tomography and tracers such as F-18 DOPA.

Physiology of normal and abnormal blinking.

Blink rate is determined by many factors, including local eye irritation, the state of the corneal tear film, factors related to general visual function, the amount of general facial movement, cognitive variables, and the level of arousal. These factors appear to be mediated by several neuroanatomic structures (Table 2). The timing and the nature of the interrelationship between neuroanatomic structures during blinking remains to be determined.

Neurotransmitter amino acids in post-mortem brains of chronic schizophrenic patients.

Neurotransmitter amino acids were measured in post-mortem caudate nucleus, nucleus accumbens, frontal cortex, amygdala, and hypothalamus of chronic schizophrenic and normal control subjects. The concentrations of upsilon-aminobutyric acid (GABA), taurine, glycine-threonine, glutamate, aspartate, glutamine, tryptophan, and alanine were similar in both groups, with the exception of decreased GABA and tryptophan in the amygdala of the schizophrenic group. Strong positive correlations were obtained between the concentration of tryptophan, a putative agonal status marker of post-mortem brain tissue, and the concentration of GABA in all brain areas.

Cortical "stress tests" in schizophrenia: regional cerebral blood flow studies.

A total of 261 regional cerebral blood flow (rCBF) studies were carried out on 34 medication-free patients with chronic schizophrenia and 50 normal subjects. rCBF, an indicator of local cortical metabolism and activity, was measured during the resting state and also during four cognitive activation tasks or "cortical stress tests." The latter included the Wisconsin Card Sort (WCS), a test of prefrontal lobe function; a simple numbers matching task, and two versions of a visual Continuous Performance Task (CPT).

Proenkephalin gene expression in the PC12 pheochromocytoma cell line: stimulation by sodium butyrate.

The differentiation promoter sodium butyrate increases the content of Met5-enkephalin-Arg6-Gly7-Leu8 (Met5-enk-RGL)-immunoreactive peptides in PC12 pheochromocytoma cells, which, unlike mature adrenomedullary chromaffin cells, contain exceedingly low levels of opioid peptides. These butyrate-induced enkephalin-immunoreactive peptides, which are specific products of the proenkephalin gene, consist principally of two high mol wt forms of amino-terminally extended Met5-enk-RGL. These high mol wt peptides, with apparent mol wt of 20,000 and 10,000, are approximately the same size as the two major immunoreactive peptides found in adult New England Deaconess Hospital rat adrenal.

Effect of gamma-aminobutyric acidA receptor agonists and antagonists on the release of enkephalin-containing peptides from dog adrenal gland.

Chromaffin cells of the adrenal medulla are known to store and release catecholamines, Met5-enkephalin (ME)-like peptides and gamma-aminobutyric acid (GABA). The present study documents that stimulation of GABAA receptors located on chromaffin cell membranes of canine adrenal glands, eliciting depolarization of chromaffin cell membranes, modulates the responsiveness of chromaffin cells to splanchnic nerve stimulation. 4,5,6,7-Tetrahydroisoxazolo[5,4-c]pyridin-3-ol (0.

Effect of chronic nicotine administration on monoamine and monoamine metabolite concentrations in rat brain.

The effects on rat brain tissue monoamine and monoamine metabolite concentrations of chronic nicotine administration at two doses (3 and 12 mg/kg/day) using constant infusion were studied. After 21 days of treatment, tissue concentrations of dopamine (DA), norepinephrine (NE), 5-hydroxytryptamine (5-HT), and several metabolites in striatum, hypothalamus, and frontal cortex were determined by high performance liquid chromatography with electrochemical detection. Compared with a control group, nicotine treatment significantly decreased NE in frontal cortex but not in other regions.

Comparative immunohistochemical demonstration of peptide F- and other enkephalin-containing neurons in the enteric nervous system of the rat.

The immunohistochemical localization of peptide F and the related enkephalins met5-enkephalin (met-enk), leu5-enkephalin (leu-enk), met5-enkephalin-arg6-phe7 (met-enk-arg-phe), and met5-enkephalin-arg6-gly7-leu8 (met-enk-arg-gly-leu) was investigated by means of the indirect immunofluorescence technique in the enteric nervous system of the rat. Peptide F-like immunoreactivity was widely distributed within neuronal structures throughout the gastrointestinal (GI) tract of the rat. Peptide F-containing nerve cell bodies were mainly located in the myenteric plexus, and only rarely were seen in the submucosal plexus.