摘要:

AbstractAt the level of the J1 joint of each antenna of the rock lobsterPalinurus vulgarisa hair plate sensory organ (hp) similar to those described in insects has been observed. Thehpis located on the internal side of the S2 segment of the antenna, close to the soft articulating membrane of the J1 joint. It is formed by a triangular surface of cuticle about 3mm2in area, covered with numerous hairs of different lengths (Figs. 1 and 2). Details of thehpwere studied by scanning electron microscopy (Fig. 2). Physiological stimulation of thehphairs occurs during medial movement of the J1 joint. Under this condition the soft articulating membrane rolls over the hairs and bends them progressively back onto the cuticle. Flexion of all the hairs corresponds to a medial movement of the J1 through 40°. During this type of movement, the number of successively flexed hairs increases linearly (Fig. 3). Electrophysiological recordings of thehpsensory nerve correlated with selective mechanical stimulation of individual hairs demonstrated that each hair is innervated by a single sensory fiber. This sensory neurone responds phasically when the hair is flexed back onto the cuticle (as during an S2 medial movement) and when it returns to its resting position (as during an S2 lateral movement). Most of the sensory neurones are sensitive to the movement velocity of the hairs (Figs. 4 and 5). When the hair is maintained flexed its sensory neurone discharges tonically (Fig. 4). Electrical stimulation of thehpsensory nerve induced reflex actions in the external and internal rotator muscles of the segment S1. These effects were found to selectively activate the tonic motor command of these muscles (Fig. 6)

ISSN:0022-3034    

DOI:10.1002/neu.480170202

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

年代:1986

数据来源: WILEY

摘要:

AbstractAxotomy of a major cranial post ganglionic branch of the superior cervical ganglion of an adult rat resulted in increased radiolabeling of tubulin and microtubule‐associated proteins after an in vitro 5‐h incubation with [14C]‐methionine. The increased incorporation of the radiolabel began at day 1 postoperatively and exhibited a biphasic response, peaking at days 3

ISSN:0022-3034    

DOI:10.1002/neu.480170203

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

年代:1986

数据来源: WILEY

摘要:

AbstractAnin vitropreparation consisting of the siphon, mantle, gill, and abdominal ganglion undergoes classical conditioning when a weak tactile stimulus (CS) applied to the siphon is paired with a strong tactile stimulus to the gill (UCS). When the stimuli are paired, the CS comes to evoke a gill withdrawal reflex (GWR) which increases in amplitude with training. Only when the stimuli are paired in a classical conditioning paradigm does the CS come to evoke a GWR. With classical conditioning training there is an alteration in the synaptic efficacy between central sensory neurons and central gill motor neurons. Moreover, these changes can be observed in sensory neurons not activated by the CS. The changes observed, as evidenced by the number of action potentials evoked in the gill motor neuron do not completely parallel the observed behavioral changes. It is suggested that in addition to changes in the synaptic efficacy at the sensory‐motor neuron synapse, other changes in neuronal activity occur at other loci which lead to the observed behavioral change

ISSN:0022-3034    

DOI:10.1002/neu.480170204

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

年代:1986

数据来源: WILEY

摘要:

AbstractActivity of Na, K‐ATPase in homogenates of fresh cerebral cortex of rats was compared with that of cortex frozen under different conditions. Activity yields after rapid in situ freezing of the exposed cerebral cortex were twice, higher (26.1 U) than in homogenates of the fresh cortex (13.3 U). Fresh brain kept on ice for 60 and 300 s and subsequently frozen in liquid nitrogen yielded activities comparable to those of the tissue frozen in situ (24.1 U and 24.9 U for 60 s and 300 s periods, respectively). Inhibition of Na, K‐ATPase by 10−7Mvanadate was significantly stronger (38%) in homogenates of the fresh brain then in those of the cortex frozen in situ (28%). High Na, K‐ATPase activity (47.6 U) in suspensions of synaptosomal membranes (SM) prepared from fresh cortical homogenates was only slightly inhibited by 10−7Mvanadate (12%). Various treatments of homogenates or SM suspensions, like increase of piston rotation speed, repeated freezing and thawing procedure or vigorous shaking did not significantly affect the enzyme activity. Mg‐ATPase activity and its sensitivity to vanadate was also modified by tissue treatment but the effect was much less

ISSN:0022-3034    

DOI:10.1002/neu.480170205

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

年代:1986

数据来源: WILEY

摘要:

AbstractPrevious clinical and experimental work has shown that increased dietary intake of choline elevates blood choline and brain acetylcholine levels. This change in neuronal acetylcholine concentration may augment learning and memory functions. We tested this prediction using the molluscLimax maximus, an animal which can be readily conditioned to avoid food odors. In our experiments, initial learning of a food avoidance task was not augmented by the high choline diet. However, the duration of memory retention was prolonged. In previous studies, we have shown that intake of the choline enriched diet significantly increases blood choline and amplifies transmission at an identified cholinergic synapse inLimax. Together, these results support the involvement of cholinergic synapses in the memory retention mechanism.

ISSN:0022-3034    

DOI:10.1002/neu.480170206

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

年代:1986

数据来源: WILEY

摘要:

AbstractRespiratory pumping of the gill and siphon ofAplysia californicais a fixed‐action pattern coordinated by a defined set of interneurons and motor neurons. In semi‐intact preparations of the gill and siphon innervated by the abdominal ganglion, respiratory pumping is facilitated for a prolonged period following activation of the peptidergic bag cell neurons. The induced changes in contractile behavior of the gill and siphon correlate with cell specific actions of the bag cells on motor neurons regulating these organs. Our results suggest that peptidergic neurons can alter the expression of a fixed pattern of behavior by modulating the excitability of motor neurons controlling the behav

ISSN:0022-3034    

DOI:10.1002/neu.480170207

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

年代:1986

数据来源: WILEY

ISSN:0022-3034    

DOI:10.1002/neu.480170201

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

年代:1986

数据来源: WILEY