Geraerts W P
Faculty of Biology, Vrije Universiteit, Amsterdam, The Netherlands.
Gen Comp Endocrinol. 1992 Jun;86(3):433-44. doi: 10.1016/0016-6480(92)90068-u.
The neuroendocrine light green cells (LGCs), 4 clusters of together approximately 150 giant neurons in the cerebral ganglia of the freshwater gastropod, Lymnaea stagnalis, have been suggested to be involved in the control of growth. The present study examines in greater detail this role and possible actions on energy metabolism. Growth indices (total body and organ wet and dry weights, as well as protein and DNA contents of the organs) and metabolic indices (tissue lipid, polysaccharide and glucose levels) were compared in LGC extirpated/reimplanted with control groups. LGC extirpation in rapidly growing juvenile snails immediately arrested growth, which was restored by reimplantation of cerebral ganglia with LGCs but not by cerebral ganglia without LGCs, indicating their neuroendocrine control of growth. The LGCs stimulate a pattern of organ growth, which is in proportion to the growth of the whole body except for the shell, which shows a disproportionally faster growth due to calcium deposition over the whole surface. The data on protein and DNA in the organs strongly suggest that the LGCs induce growth by stimulating cell multiplication. The LGCs maintain low tissue glycogen reserves and hemolymph concentrations of both glycogen and glucose. The secretions of these cells stimulate the uptake of glucose by the growing tissues with no apparent effects on lipid metabolism.
在淡水腹足纲动物椎实螺的脑神经节中，神经内分泌浅绿色细胞（LGCs）由4个细胞簇组成，共计约150个巨型神经元，有人认为它们参与生长控制。本研究更详细地探讨了这一作用以及对能量代谢的可能影响。对切除/重新植入LGCs的实验组与对照组的生长指标（整体及器官的湿重和干重，以及器官的蛋白质和DNA含量）和代谢指标（组织脂质、多糖和葡萄糖水平）进行了比较。在快速生长的幼螺中切除LGCs会立即停止生长，而重新植入含有LGCs的脑神经节可恢复生长，不含LGCs的脑神经节则不能，这表明它们对生长具有神经内分泌控制作用。LGCs刺激一种器官生长模式，这种模式与除贝壳外的全身生长成比例，贝壳由于整个表面的钙沉积而生长速度不成比例地更快。器官中蛋白质和DNA的数据强烈表明，LGCs通过刺激细胞增殖来诱导生长。LGCs维持低水平的组织糖原储备以及血淋巴中糖原和葡萄糖的浓度。这些细胞的分泌物刺激生长组织对葡萄糖的摄取，对脂质代谢无明显影响。
