Petri Bernhard, Homberg Uwe, Loesel Rudolf, Stengl Monika
Institut für Zoologie/Biologie I, Universität Regensburg, 93040 Regensburg, Germany.
J Exp Biol. 2002 May;205(Pt 10):1459-69. doi: 10.1242/jeb.205.10.1459.
Accumulating evidence suggests that the accessory medulla is the location of the circadian pacemaker in the fruit fly Drosophila melanogaster and the cockroach Leucophaea maderae. gamma-Aminobutyric acid (GABA) and Mas-allatotropin are two putative neurotransmitters, in the accessory medulla in the cockroach Leucophaea maderae. Neurons immunoreactive to the neuropeptide Mas-allatotropin are local neurons with arborizations in the noduli of the accessory medulla, while GABA-immunoreactive neurons connect the noduli of the accessory medulla to the medulla and to the lamina via processes in the distal tract. Injections of GABA and Mas-allatotropin into the vicinity of the accessory medulla resulted in stable phase-dependent resetting of the circadian locomotor activity of the cockroach. The resulting phase response curves closely matched light-dependent phase response curves, suggesting that both substances play a role in circuits relaying photic information from circadian photoreceptors to the central pacemaker.
越来越多的证据表明，副髓质是果蝇黑腹果蝇和蟑螂马德拉蜚蠊昼夜节律起搏器的所在位置。γ-氨基丁酸（GABA）和促咽侧体素是蟑螂马德拉蜚蠊副髓质中的两种假定神经递质。对神经肽促咽侧体素免疫反应阳性的神经元是局部神经元，其树突分支位于副髓质的小结中，而GABA免疫反应阳性的神经元则通过远侧束中的突起将副髓质的小结与髓质和层板相连。向副髓质附近注射GABA和促咽侧体素会导致蟑螂昼夜运动活动出现稳定的相位依赖性重置。由此产生的相位反应曲线与光依赖性相位反应曲线紧密匹配，这表明这两种物质在将光信息从昼夜节律光感受器传递到中央起搏器的回路中发挥作用。
