ISSN:0022-3034    

DOI:10.1002/neu.480050102

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

年代:1974

数据来源: WILEY

摘要:

AbstractThe neural plexus in theAplysiagill is comprised of monopolar, bipolar, and multipolar neurons. Histochemical procedures reveal acetycholinesterase (AChE), serotonin (5HT), and possibly dopamine present in plexus neurons. The three cell morphologies in the plexus are found in specific regions of the gill. Monopolar cells singly and in clusters lie along branches of the branchial and ctenidial nerves. The largest cluster, the gill ganglion, is located on the branchial nerve; ganglion neurons show a marked similarity to neurons in the central nervous system. AChE is present in monopolar neurons; its presence was demonstrated using acetylthiocholine as a substrate with inhibitors specific for esterases other than AChE. Monoamines are also contained in monopolar cells; yellow and green fluorescence, resulting from exposure to paraformaldehyde vapor, indicated that 5HT and catecholamines, respectively, are present in the cells. Bipolar neurons, containing AChE, are located beneath the ciliated epithelium in the pinnule. Multipolar, monopolar, and bipolar cells are found in the gill musculature. Single neurons appear to innervate at least two muscle bundles. Evidence is also presented suggesting that cells containing different neurotransmitters can terminate in the same muscle. Acetylcholine, 5HT, and dopamine, when infused in the gill, elicited discernable movements for each agent. The plexus, with its apparent hierarchy of neurons, has a number of properties ascribed to the central nervous system. The hierarchy is discussed in relation to the physiology of plexus neurons and to the behavior manifested by the gill.

ISSN:0022-3034    

DOI:10.1002/neu.480050103

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

年代:1974

数据来源: WILEY

摘要:

AbstractThe abdominal and pedal‐pleural ganglia ofAplysia californicawere maintained in organ culture for periods up to 45 days. Neurophysiological examination of abdominal ganglia indicated that synaptic activity could be evoked in ganglia cultured for 21 days and action potentials and spontaneous postsynaptic potentials persisted for 45 days. The effects of long‐term culture on neurotransmitter metabolism were studied by measuring the activities of ChAc, AChE, AAD, and COMT in both cultured abdominal and pedal‐pleural ganglia. G‐6‐PD and CarnAc activities were also measured. In general, the stabilities of the enzymes in abdominal ganglia toin vitroconditions were similar to those in pedal‐pleural ganglia. None of the enzymes studied were markedly affected by culture conditions for at least fourteen days. After this time, enzymes involved in neurotransmitter synthesis, AAD and ChAc, exhibited fairly abrupt decreases in activity. The degradative enzymes studied, AChE and COMT, showed more gradual decreases in activity. The changes occurring in the neurotransmitter metabolizing enzymes after prolonged periods of time in culture are discussed in relation to the neurophysiological changes which we

ISSN:0022-3034    

DOI:10.1002/neu.480050104

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

年代:1974

数据来源: WILEY

摘要:

AbstractIsolated somata of identified motorneurons in the metathoracic ganglion of the locust were analyzed for glutamate decarboxylase (GAD), choline acetyltransferase (ChAc), acetylcholinesterase (AChE), and aromatic amino acid decarboxylase (AAD). Isolated inhibitory motorneuron somata have GAD activity but those of excitatory motorneurons do not. Since this enzyme is responsible for the synthesis of gamma amino butyric acid there is a metabolic basis for these motorneurons to accumulate GABA. In contrast to the specific localization of GAD in inhibitory motorneurons, AChE was found in large amounts in all motorneurons tested. The specific activity of ChAc and AAD in both inhibitory and excitatory motorneurons were similar or lower than the specific activity of the whole ganglion. Degeneration experiments suggest that ChAc is mainly localized in the sensory neurons.

ISSN:0022-3034    

DOI:10.1002/neu.480050105

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

年代:1974

数据来源: WILEY

摘要:

AbstractThe excitatory and inhibitory postsynaptic responses ofAplysiaganglion cells were elicited by either stimulating cholinergic afferent fibers or by topically applying acetylcholine (ACh) to the cell under study. The responses were evaluated as an increase in membrane conductance and compared before, during, and after perfusion with Li+‐Ringer. Excitatory postsynaptic responses were significantly depressed during 30–60 min of Li+‐Ringer perfusion. Upon return to normal Ringer, they increased sharply beyond the control, showing post‐Li+augmentation.Inhibitory postsynaptic responses were augmented during 30–60 min of Li+‐Ringer perfusion when the cells were examined before treatment with anticholinesterase. After treatment with neostigmine, however, they were found to be also depressed in Li+‐Ringer. This finding suggested a suppressing effect of Li+‐Ringer on the acetylcholinesterase (AChE) activity.The reversal potential of ACh‐induced depolarizing response was altered from the normal value of –25 mV to –5 mV during 1–2 hr of Li+‐Ringer perfusion and gradually returned to normal value in 2–3 hr after return to normal Ringer. The reversal potential of ACh‐induced hyperpolarizing response remained practically unchanged (–62 mV) during 1–2 hr of Li+‐Ringer perfusion.Post‐Li+augmentation of ACh‐induced depolarizing responses was explained by an increase in driving force for Na+movement resulting from a depletion of intracellular Na+. The systematic shift of the dose‐response curves during Li+‐Ringer perfusion suggested that the affinities of both excitatory and inhibitory receptors to ACh are depressed and the ef

ISSN:0022-3034    

DOI:10.1002/neu.480050106

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

年代:1974

数据来源: WILEY

摘要:

AbstractChromaffin cells were studied by fluorescence microscopy in long‐term cell cultures of dissociated chick embryo sympathetic ganglia. These cells were distinguishable in culture from the sympathetic ganglionic neurons by their small size, relative infrequency of occurrence, intense fluorescence and survival in the absence of nerve growth factor (NGF). By several weeks in culture, with or without NGF in the medium, the chromaffin cells produced extensive ramifications of fluorescent varicose processes. It is suggested that at least part of the intraganglionic system of adrenergic varicose terminals arises from chromaffin cells. This capability with regard to fiber production lends credence to the suggestion that chromaffin cells may play an active role in ganglionic functio

ISSN:0022-3034    

DOI:10.1002/neu.480050107

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

年代:1974

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480050108

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

年代:1974

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480050101

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

年代:1974

数据来源: WILEY