摘要:

AbstractIn the temperature sensitive mutant ofDrosophila, shibirets1(shi), synaptic transmission in the dorsal longitudinal flight muscles (DLM) is normal at 19°C, but is diminished progressively as the temperature is raised, and is blocked at 29°C. The purpose of this paper is to determine whether this defect is located presynaptically, postsynaptically, or both. It is demonstrated here that the postsynaptic sensitivity to L‐glutamate, the putative transmitter for this synapse, is not decreased at 29°C. Furthermore, studies conducted with genetic mosaics of this mutant show that transmission is blocked when a mutant motor neuron synapses on a wild‐type muscle fiber, but is not blocked when a wild‐type motor neuron synapses on a mutant muscle fiber. Thus, theshiphenotype (temperature dependent transmission block) correlates with ashimotor neuron, not with ashimuscle fiber. The data, therefore, suggest that the defect is not postsynaptic, but pre

ISSN:0022-3034    

DOI:10.1002/neu.480140602

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

年代:1983

数据来源: WILEY

摘要:

AbstractInfluence of walking on swimmeret beating in intact lobsters,Homarus gammarus, has been analyzed using a treadmill experimental device. Belt movement activates both leg stepping and swimmeret beating. The simultaneity of the onset of the two motor systems in this situation is demonstrated to be the result of a startle response initiated when the belt begins to move. This reaction consists of a non‐specific motor activity involving several antagonist postural and dynamic muscles. Abdominal extension and vigorous swimmeret beating are the main featurs of this reaction. The main characteristics of the swimmeret beating as defined by Davis (1969) has been observed here in sequences without walking. However during long walking sequences a very different swimmeret beating pattern occurs. It is suggested that this slow swimmeret beating is completely subordinate to the walking rhythm during sequences of absolute coordination. In more rapid swimmeret beating a relative coordination with leg stepping is very common. The functional meaning of this linkage between legs and swimmerets is discusse

ISSN:0022-3034    

DOI:10.1002/neu.480140603

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

年代:1983

数据来源: WILEY

摘要:

AbstractIntersegmental interneurons in the lobster second abdominal ganglion were differentially stained by simultaneously backfilling their axons in the anterior and posterior hemiconnectives with nickel and cobalt ions. When precipated with rubeanic acid the nickel and cobalt formed different colors in the cell bodies depending upon the location of the axon(s) in the connectives. In the most completely stained preparations 55 ascending, 56 descending, and 25 bidirectional interneurons were observed. Soma diameters ranged from 157ndash;120 μm. One of the somata was located in the connective. The differential staining technique has advantages over conventional backfilling techniques for examining the morphological relationships of populations of neurons having different axon projections

ISSN:0022-3034    

DOI:10.1002/neu.480140604

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

年代:1983

数据来源: WILEY

摘要:

AbstractThe effect of fatty acids on the membrane fluidity in tissue cultured chick embryo dorsal root ganglion was studied by fluorescence recovery method. Lateral motion of the lipid was measured by observing the fluorescent probe, 5‐(octadecylthiocarbamoylamino) fluorescence, F18. The effective lateral diffusion coefficient of the membrane was around 0.30 × 10−8cm2/sec in control cells, 0.42 × 10−8cm2/sec in 2‐decenoic acid treated cells, and 0.35 × 10−8cm2/sec in valeric acid treated cells. From these results it is concluded that effective mobilities of the membrane complex increased about 40% by the external application of 2‐decenoic acid, while valeric acid increased it only 12%. From the physiological results that 2‐decenoic acid inhibits the Na‐channel, it is suggested that this increase in the membrane fluidity might aff

ISSN:0022-3034    

DOI:10.1002/neu.480140605

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

年代:1983

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480140606

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

年代:1983

数据来源: WILEY

摘要:

AbstractThe rate of regeneration of rat sciatic nerve sensory axons was measured using the pinch‐reflex test method, and confirmed by studying the transport of labelled protein into the regenerating axons. For nerves receiving a single test crush lesion the rate was 4.02 ± 0.03 (SE) mm/day. For nerves with a conditioning lesion made at the knee seven days prior to the test lesion at the hip the rate was 5.73 ± 0.06 mm/day, and for nerves where both conditioning and test lesions were made at the same site (hip or knee) but separated by seven days, the rate was 6.76 ± 0.04 mm/day, a 68% increase over the normal rate, showing that pre‐degeneration of the nerve distal to the site of the test lesion increases the rate of regeneration. It is concluded that the rate of axon regeneration can be influenced by the environment through which the regenerating axon

ISSN:0022-3034    

DOI:10.1002/neu.480140607

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

年代:1983

数据来源: WILEY

摘要:

AbstractWe have identified a cluster of neurosecretory cells in the crayfish eyestalk that possess dendrites in the second optic neuropil (Medulla) and project axons to the first optic neuropil (Lamina). Illumination of the ipsilateral retina produces a synaptic inhibition of these cells that is mimicked by iontophoresis of gamma‐aminobutyric acid within the medullary neuropil. The neurosecretory nature of the cells, the efferent projection of their axons, and the strong inhibition of their spiking activity upon retinal illumination suggest that they may be involved in the feedback control of dark adaptation and/or circadian changes in visual sensitivit

ISSN:0022-3034    

DOI:10.1002/neu.480140608

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

年代:1983

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480140609

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

年代:1983

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480140610

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

年代:1983

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480140611

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

年代:1983

数据来源: WILEY