Research of generation of respiratory rhythm

这三个神经元组成了蜗牛大脑中的呼吸中枢模式发生器。并对其功能进行了研究。当将低氧盐水溶液灌注在分离的脑制备物上时（即，没有外周神经），呼吸活动保持不变。当将低氧盐水溶液灌注在半完整的脑制备物上时（即，右足1背侧I呼吸神经元然后分离并培养RPeD 1（RPeD 1，其启动呼吸活动）。用低氧盐水溶液灌注不产生静息膜或动作电位的变化，表明RPeD 1不表现出氧化学感受。尝试分离和培养位于肺口正下方的卵巢桡神经节的神经元。二氧化碳对分离的和半完整的脑制备物的影响也通过用5%CO2/95%O2气体混合物平衡的盐水溶液灌注来检查。为了区分pH的影响与CO2的存在，用用21%O2 + 79%NO2平衡的盐水溶液灌注两种制剂，并用HCl将其pH调节至7.0-7.5。两种制剂中的呼吸活动也降低。

The three neurons that comprise the respiratory central pattern generator in the brain of the snail. Lymnaea stagnalis were examined to elucidate their function. When an hypoxic saline solution was perfused over an isolated brain preparation (i.e., without peripherally nerves), respiratory activity remained unchanged When an hypoxic saline solution was perfused over a semi-intact brain preparation (i.e., peripherally nerves still connected), respiratory activity increased.The Right Peda1 Dorsal I respiratory neuron (RPeD1, that initiates respiratory activity) was then isolated and cultured Perfusion with an hypoxic saline solution produced no change in either the resting membrane or action potentials, suggesting that RPeD1 does not exhibit oxygen chemoreception.To locate and isolate the oxygen chemoreceptor, an attempt was made to separate and culture the neurons of the osphradium ganglion, which lies immediately beneath the pneumostome. All attempts thus far have been unsuccessful.The effects of carbon dioxide on both the isolated and semi-intact brain preparations were also examined by perfusing them with a saline solution equilibrated with a 5% C02/95% 02 gas mixture. Respiratory activity decreased in both preparations.The saline solution used in the experiment above also had a low pH.In an effort to distinguish the effects of pH from the presence of C02, both preparations were perfused with a saline solution equilibrated with 21%02+79%N02 and whose pH had been adjusted with HCl to a pH of 7.0-7.5. Respiratory activity was decreased in both preparations as well.