摘要:

AbstractCholine Acetyltransferase (CHAc) activity has been estimated using a microradiochemical method in short segments of rat sciatic nerve at different times after crushing the nerve once or with a second crush 2 cm distal to the first. Above a single or proximal crush, the CHAc levels rose slowly in the 5 mm immediately above the crush to reach about 1 1/2 times control at 24 hr. Distal to a single crush and between two crushes no change was detected in CH‐Ac‐activity up to 18–24 hr. The results are discussed in relation to the rapid accumulation of acetylcholine (ACH) above a crush, and redistribution between two crushes which have previously been demonstrated in the same preparation. It is concluded that the rate of transport of CHAc is probably much slower than that of ACH, and that their mechanismes of transport are not the

ISSN:0022-3034    

DOI:10.1002/neu.480040202

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

年代:1973

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480040203

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

年代:1973

数据来源: WILEY

摘要:

AbstractCells from brains of fetal rats were grown in surfece cell culture for up to 46 days and were subjected to two subculturing cycles with mild trypsin treatment. The cells maintained their characteristic morphology into third passage, and some putative neurons developed the ability to abhere directly to plastic surfaces. The specific activity of choline acetyl‐transferase reached higher levels in third than in first passage cultures. An increase of at least 34‐fold was obtained in the total activity of enzyme, the major increments occurring during first and third passages. The data suggest that choline acetyltransferase‐producing cells may be capable of multiplication in cu

ISSN:0022-3034    

DOI:10.1002/neu.480040204

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

年代:1973

数据来源: WILEY

摘要:

AbstractTreatment with lidocaine, at exposures which completely block impulse conduction and rapid axonal transport, resulted in a sequence of morphological effects on rabbit vagus neverin vitro. Low exposures (0.3% for 90 min, 0.4% for 45 min, 0.6% for 25 min) caused a reorientation and proliferation of smooth endoplasmic reticulum (SER); the number of axonal microtubules either remained normal or was increased. Intermediate exposures (0.4% for 90 min, 0.6% for 45 min) Produced a similar effect on the SER, as well as causing a 50% reduction in microtubule number and some swelling of axons and Schwann cells. The highest exposure (0.6% for 75 min) caused over 90% reduction in microtubule number, a partial loss of neurofilaments, and severe swelling of axons, Schwann call, and mitochondria. Reversibility of these effects was tested in lidocaine‐treated nerves that had been washed with fresh culture medium. There was good recovery of nerve exposures. After intermediate exposures, there was only partial return of rapid transport, even though imposures, there was morphological, and no recovery occured throughout the excised vagus nerve in efferent and afferent axons as well as Schwann cells, and these events did not coincide with changes in the functional state of rapid axonal transpor

ISSN:0022-3034    

DOI:10.1002/neu.480040205

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

年代:1973

数据来源: WILEY

摘要:

AbstractLabeled components, carried by axoplasmic transport into the cat dorsal roots and sciatic nerves following injection of3H‐leucine into the lumbar seventh (L7) dorsal root ganglia, were studied. The pattern of activity present in the subcellular fractions was similar for the two branches of the ganglion neurons entering the nerve and the dorsal root.Fractionation of the proteins present in the high speed supernatant fraction shows that slow transport carries a major proportion of high molecular weight soluble proteins. Further fractination of the soluble proteins with Sephadex G‐200 showed labeled activity present in three peaks: Ia, proteins of 480,000 M. W., lb, proteins of 60,000–120,000 M. W. containing colchicine binding (microtubular) protein, and peak II polypeptides, 5,000–10,000 M. W.Isoelectrofocusing of la proteins gave three peaks at pl 4.0, 4.05, and 4.15, and of lb proteins gave peaks at pl 4.0, 4.45, and 4.8 with several minor peaks also present. A gradual shift in pl values of the labeled proteins from acidic to neutral pH was seen from 3 hr to 7 days after the injections.A small amount of soluble proteins and some free leucine is carried down by fast transport, which is characterized by a high amount of activity in the particulate component. A comparison of the distribution of labeled incorporation in the crest and plateau region of fast transported materials showed a somewhat smaller percentage of activity in the small particulate fraction in the plateau, with more labeling of the soluble fraction and with no free leucine present.The results are in conformity with the concept of a compartmentalization of incorporated proteins in the cell body from which materials of somewhat different compositions later enter the axon for tr

ISSN:0022-3034    

DOI:10.1002/neu.480040206

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

年代:1973

数据来源: WILEY

摘要:

AbstractSomata of 26 of the motorneurons situated on the right side of the metathoracis ganglion of the locustS. gregariawere identified by correlating their electrical activity with extracellularly or intracellularly recorded muscle potentials evoked either reflexly or by direct elctrical stimulation of the somata through the recording microelectrode. The neurons identified included most of those innervating the major leg muscles. Each neuron occupies a relatively fixed site on the ventral surface of the ganglion. The identified neurons were filled with procion yellow, the ganglia fixed and photographed as whole mounts, and then serially sectioned to determine the three dimensional topography of the major dendrites and the pathway of the axons through the neuropil. The topographical features of individual motorneurons were sufficiently characteristic to permit identification, Nevertheless, it was not found possible to classify the neurons on the basis of branching pattern. There is no relation between location in the ganglion and the muscle innervated, but locomotor motorneurons are clustered togethers in anterior, ventral, and lateral pockets.

ISSN:0022-3034    

DOI:10.1002/neu.480040207

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

年代:1973

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480040201

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

年代:1973

数据来源: WILEY