Merz D C, Drapeau P
Centre for Research in Neuroscience, McGill University, Montreal, Quebec, Canada.
Proc Biol Sci. 1992 May 22;248(1322):129-33. doi: 10.1098/rspb.1992.0052.
Serotonergic Retzius (R) neurons of the leech form a Cl-dependent synapse with pressure-sensitive (P) neurons both in vivo and in vitro. However, P cells show an extrasynaptic, cationic response to application of 5-hydroxytryptamine (5-HT) which is reduced upon contact between the neurons in culture. We have examined the cellular specificity of the selection of 5-HT responses in the P cell by pairing it in culture with a variety of identified neurons. Non-synaptic sensory cells, non-serotonergic pre- and postsynaptic partners and serotonergic neurons that do not form chemical synapses with the P cell failed to alter its responses to 5-HT. The selective reduction of the extrasynaptic response to 5-HT in the P cell therefore appears to be induced specifically by contact with its only known serotonergic partner during neuronal recognition leading to synapse formation.
水蛭的5-羟色胺能Retzius（R）神经元在体内和体外均与压力敏感（P）神经元形成氯离子依赖性突触。然而，P细胞对应用5-羟色胺（5-HT）表现出一种突触外的阳离子反应，在培养物中神经元接触时这种反应会减弱。我们通过在培养物中将P细胞与各种已鉴定的神经元配对，研究了P细胞中5-HT反应选择的细胞特异性。非突触感觉细胞、非5-羟色胺能的突触前和突触后伙伴以及不与P细胞形成化学突触的5-羟色胺能神经元均未能改变其对5-HT的反应。因此，P细胞中对5-HT突触外反应的选择性降低似乎是在神经元识别导致突触形成的过程中，由与其唯一已知的5-羟色胺能伙伴接触特异性诱导的。
