. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 3nA. 3nA RB1 / Mg++ Ca++ LA6. +3nA + 3nA Figure -4. (A. B) Each spike in the CAB neuron produced individual excitatory postsynaptic potentials in A and B neurons with stable short latencies even in high Mg* '/high Ca* * solution. Scale bars = 10 m V, 50 ms. (C) High Mg' f/high Ca++ saline did not influence any of the types of postsynaptic potentials in A and B motoncurons after CAB neuron activation. Scale bars = 15 mV, 1 s. tivity in CAB neurons (Fig. 6A), suggesting that electrical coupling plays an important role in synch
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 3nA. 3nA RB1 / Mg++ Ca++ LA6. +3nA + 3nA Figure -4. (A. B) Each spike in the CAB neuron produced individual excitatory postsynaptic potentials in A and B neurons with stable short latencies even in high Mg* '/high Ca* * solution. Scale bars = 10 m V, 50 ms. (C) High Mg' f/high Ca++ saline did not influence any of the types of postsynaptic potentials in A and B motoncurons after CAB neuron activation. Scale bars = 15 mV, 1 s. tivity in CAB neurons (Fig. 6A), suggesting that electrical coupling plays an important role in synchronizing activ- ities of contralateral CAB neurons. B motoneurons did not induce responses in cerebral CAB neurons, whereas strong activation of A motoneurons produced inhibitory inputs in CAB neurons (Fig. 6B). This connection was not monosynaptic, because individual spikes in A neurons did not produce individual inhibitory postsynaptic potentials in CAB neurons, and only strong burst activity was able to induce CAB neuron inhibition. These inhibitory inputs presumably serve as negative feedback, preventing reverberation of impulses between the two groups of neurons. As previously mentioned, mechanical contact with prey produces significant sensory inputs that initiate buccal cone extrusion. Tactile stimulation of the anterior region of the head, including the lips, produced excitatory inputs in CAB neurons that were able to initiate spike activity in CAB neurons (Fig. 7). Thus, CAB neurons, which produce co-activation of A and B motoneurons, are included in the neuron pathway that underlies the rapid extrusion of buccal cones initiated by mechanical inputs from the prey. Discussion Expansion of the buccal cones of Clionc is a hydraulic phenomenon accomplished through squeezing of hemo- coelic fluid from the head hemocoel into the hemocoelic cavities of the buccal cones. Ordinarily, such hydraulic inflation of tentacular structures is a relatively slow pro- cess, as seen in th
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
