摘要:

AbstractThis study was directed toward a comparison of the effectiveness of three different light‐microscopical methods for identifying and studying the features of cells that contain horseradish peroxidase (HRP) granules. The cells studied were located in the trigeminal ganglia and were labeled after the injection of HRP solutions into single, maxillary, canine teeth. The tissue was examined with light field, dark field, and differential interference optics systems. The results indicated that differential interference optics were especially useful in revealing the presence of intracellular HRP granules in both unstained and stained tissue, particularly when cells only contained small amounts of HRP. It was also noted that a wide variety of quantitative analyses could be performed with differential interference optics, even when using unstained tissu

ISSN:0360-4012    

DOI:10.1002/jnr.490030502

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractPharmacological, electrophysiological, and biochemical studies have been conducted with rats in an attempt to demonstrate that some of the behavioral effects of nicotine may involve non‐cholinergic brain sites. The behavioral response consisted of a prostration‐immobilization syndrome following the injection of 1−10 μg of nicotine into the region of the lateral or third transmitters and their antagonists, and a number of other psychotropic drugs were ineffective in either enhancing or antagonizing the action of nicotine. Associated with the behavioral response were distinct electrophysiological patterns recorded from electrodes implanted in the dorsal hippocampus in freely moving rats. The characteristic electrical changes consisted of shifts in the frequency from 6 to 8 per second to 2 to 4 per second, and shifts in the amplitude from 300 to 400 μV to 100 to 200 μV. A number of derivatives of nicotine and piperidine were synthesized which were found to be antagonistic to the psychopharmacological and electrical effects of nictotine. The natural (−)‐nicotine isomer was found to be at least 100 times as effective as the (+)‐nicotine on the brain. It was not possible to demonstrate3H nicotine bending to neural membrane preparations; however, the sereospecific nicotine binding was demonstrable in fresh brain slices and to glass filters. The Kbwas 2.0 ×

ISSN:0360-4012    

DOI:10.1002/jnr.490030503

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractAcetylcholinesterase (AChE) activity in dog plasma is significantly higher than in either ventricular or cisternal CSF. However, since protein levels in plasma are about 100‐fold higher than in CSF, the specific activity of AChE is lower in plasma than in CSF. Acetylcholinesterase activity in plasma represents only 22% of total cholinesterase (ChE) activity, while preliminary findings indicate that in ventricular CSF it is 50–60%. Acetylcholinesterase activity in ventricular CSF is significantly lower than in cisternal CSF. Chlorpromazine (10 mg/kg, intravenous), a drug which increases acetylcholine turnover, increased AChE‐specific activity in all dogs. Our results support the hypothesis of a neuronal origin of AChE activity i

ISSN:0360-4012    

DOI:10.1002/jnr.490030504

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractBecause sialic acid is a potential biochemical marker of membrane development or alteration, we compared acute and chronic ethanol effects on sialic acid. Experiments were conducted with 50 adult male Wistar rats (∽400 gm), housed in groups of five. Rats drank ad libitum a vitamin‐fortified diet (Nutrament) that was adulterated with ethanol; ethanol intake averaged for each rat 10–18 gm/kg/day. Controls were fed an equal total volume, made isocaloric with sucrose. Rats were sacrificed weekly for four weeks, and an acute challenge dose of ethanol (2 gm/kg, intraperitoneally) was given 45 minutes before sacrifice of both control and ethanol‐consuming rats. Some controls were challenged only with saline. We replicated our earlier findings of regional differences in sialic acid and in cerebellar deoxyribose (measured as a necessary adjunct in the autoanalyzer modification of the Warren‐Delmotte methods).In the saline‐challenged controls, levels of both compounds were higher at four weeks than after one week. Similar increases occurred also in the chronic ethanol‐consuming group, but not in the ethanol‐challenged controls, which had significantly lower values. Results in saline‐challenged controls suggest that the chronic treatment either 1) created a tolerance which protected cells from damage by the challenge dose of ethanol, or 2) killed neurons, thus promoting proliferati

ISSN:0360-4012    

DOI:10.1002/jnr.490030505

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractPrevious research with two biochemical markers of acute ethanol damage (sialic acid and 2‐deoxyribose) raised the possibility that tolerance developed by chronic ingestion of ethanol. However, this hypothesis required demonstration that chronic consumption was not damaging. This issue was investigated histologically in adult rats that voluntarily consumed massive doses of ethanol daily (range of 11 to 18 gm/kg/rat/day) for 28 days. By all indices (thickness measures of neocortex, hippocampus, and cerebellar molecular layer; and specific cell counts of neocortex and cerebellum), none of the ethanol‐exposed rats, even those with intentional nutritional deficiencies, revealed any physical sign of damage compared to control r

ISSN:0360-4012    

DOI:10.1002/jnr.490030506

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractThe concentration of glutamic acid decarboxylase (μmoles of glutamic acid decarboxylated/hr/gm) was found higher in the anterior midbrain than in several other regions of the adult rat brain. It was the highest in the anterior colliculus.A developmental study of the forebrain, cerebellum, anterior midbrain, and posterior midbrain showed that the four regions behaved as distinct organs as regards the deposition of structural constituents and the activity of glutamic acid decarboxylase. There was evidence of postnatal cell acquisition by the four regions. The rate of accretion of DNA, RNA, phospholipid, and protein was the highest in the cerebellum, but that of glutamic acid decarboxylase was highest in the forebrain during postnatal development. The results indicated that the average size of the cerebellar cell in the adult rat was smaller than that of the cell of the forebrain, anterior midbrain, and posterior midbrian. The phospholipid content compared to that of protein was higher in the posterior midbrain than in the other three brain regions.The presence of fully differentiated GABAergic neurons in the cerebellum appear by the end of the first postnatal week

ISSN:0360-4012    

DOI:10.1002/jnr.490030507

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractA new approach to study the effect of ischemia on the brain of the awake gerbil is described. The measurement of NADH fluorescence from the surface of the cortex is done by a time‐sharing fluorometer/reflectometer connected to the brain via a flexible light guide and an implanted cannula. The response of the gerbil brain to anoxia and spreading depression is described. By unilateral occlusion of the carotid artery and increase in NADH was measured in the ipsilateral hemispher

ISSN:0360-4012    

DOI:10.1002/jnr.490030508

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractPrevious observations have demonstrated decreased in vivo and in vitro protein synthesis by brain ribosomal systems following long‐term ethanol ingestion. For further investigation of the properties of brain ribosomes, the 40S and 60S ribosomal subunits were successfully isolated from control and chronic 10% ethanol‐drinking rats. For a successful dissociation of ribosomes into subunits NH4CI, puromycin and a high‐salt treatment at 10°C were essential with a critical concentration of Mg2+since ribosomes could not be resolved at less than 7 mM Mg2+. Analysis of the A260profile of the subunits on the sucrose gradients showed no significant differences between the control and ethanol‐ingesting groups. Studies on3H‐labeled ribosomes following in vivo RNA labeling showed correspondence of the radioactive profiles from the incorporation of [5‐3H] orotic acid into RNA with the sucrose gradient absorbance profile of 60S and 40S ribosomal subunits. Furthermore, active reassociation of both subunits occurred at 37°C as demonstrated by the increased [14C]‐phenylalanine incorporation in the presence of poly(U). Results further showed that the poly(U)‐dependent [14C] phenylalanine incorporation was significantly reduced by the subunits from the ethanol‐ingesting animals. These findings suggest that long‐term ingestion of ethanol caused functional changes in the properties of brain ribosomes, specifically on the reassociation proces

ISSN:0360-4012    

DOI:10.1002/jnr.490030509

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractThe present paper deals with the study of the structure of horizontal neuron chains, one of the aspects of intracortical intraneuronal relationships. The motor cortex (field 4) of cats and lower monkeys (Papio hamadryas and Macacus rhesus s. M. Mullata) was treated by the impregnating method of Golgi‐Kopsh. The drawings of neurons from 90‐μm sections were made by means of a camera lucida.Three possible pathways of impulse transmission along neuron chains in a horizontal direction were revealed. These were: a pyramido‐pyramidal system of connections which may possibly spread excitatory influence among several columns; a basket‐pyramidal connection system; and connections which arise from successive switchings between neighboring neurons of o

ISSN:0360-4012    

DOI:10.1002/jnr.490030510

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY

摘要:

AbstractAdult female Sprague Dawley rats were divided into three groups and given two daily doses of: 1) morphine (25 mg/kg at each injection), or 2) methadone (5 mg/kg), or 3) saline for nine days. Two hours before the rats were killed on day 10, they were given a double dose of the drugs. Fifteen minutes before being killed, some of the morphine‐treated rats were given the opiate antagonist naloxone (2.5 mg/kg), which caused a sudden arousal in these rats. At the time of killing, the preoptic‐hypothalamic region was rapidly removed and frozen in liquid propane to prevent translocation of elements in cells. Frozen 4‐μm sections were cut, freeze‐dried, and electron‐probed in a scanning electron microscope, and energy‐dispersive x‐ray spectra were collected. The characteristic peak‐to‐continuum ratio for all detectable elements was determined in both the nucleus and the cytoplasm of ependymal cells and neurons. The data from nine cells of each type in each rat brain were then subjected to one‐ and three‐way analysis of variance. The results show significant differences in the distribution of elements (sodium, magnesium, phosphorus, sulfur, chlorine, potassium, and calcium) which are dependent upon: 1) subcellular localization, 2) cell type, and particularly, 3) opiate treatment. The behavioral state produced by the opiate is correlated with the effects they have on intracellular concentration of several elements

ISSN:0360-4012    

DOI:10.1002/jnr.490030511

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1978

数据来源: WILEY