In your distinctive brain mobile phone , the prongy dendrite incur electric signals from other neurons , and once they ’re swear out , these signaling are passed on to other neurons along the axone , a long extension of the cell . Now , researchers have discovered a brain cadre shape that has never been seen before – where the axon arises directly from one of the dendrite . Thefindingswere published inNeuronlast week .
The axone and dendrite are usually connected by the nerve cell ’s cadre body . Rather than conduct signals via the neuron ’s center , these unusual nerve cellular phone take a cutoff to transmit information : The signals go around the cell like a bypass road . " Input signalize at this dendrite do not need not be propagated across the cellphone body , " explains study authorChristian Thome of Heidelberg Universityin anews release . And they ’re more expeditiously forwarded than signaling fall from elsewhere .
The squad colored the position of origin of axone of pyramidal cells in the hippocampus , a brainiac region take in memory . In more than half of the cells , they rule that the axone does n’t come forth from the mobile phone eubstance but originates at a dendrite instead . Then , to study the effect of signals received at these axone - carry dendrites , the team injected a neurotransmitter called glutamate into the mastermind tissue paper of mice that can be activated by clear pulses . Using a high - resolution microscope , the team directed the light beam of light forthwith to a specific dendrite , and then trigger off the neurotransmitter to assume an input signaling .
“ Our measurement indicate that dendrites that are directly connect to the axone , actively propagate even small input stimuli and trigger off the neuron,“saysstudy authorTony Kelly from University of Bonn . They call it “ inside synaptic input . ”
Using computer pretense , the squad predicts that this force is particularly pronounce when the information flux from other dendrites to the axon is inhibit by repressing input signals at the cell body . " That way,”Kelly adds , “ data transmitted by this particular dendrite influences the behavior of the nerve cell more than input from any other dendrite . ”
To figure out why these unusual shapes are there , the squad is now looking for the biologic subprogram that are strengthen through these sorts of dendrites .
