Calcium Imaging Analysis of Cellular Responses to Hypercapnia and Hypoxia in the NTS of Newborn Rat Brainstem Preparation.
Calcium Imaging Analysis of Cellular Responses to Hypercapnia and Hypoxia in the NTS of Newborn Rat Brainstem Preparation.
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DOI：
10.3389/fphys.2021.645904
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发表时间：
2021
影响因子：
4
通讯作者：
Okada Y
中科院分区：
文献类型：
--
作者：
Onimaru H;Yazawa I;Takeda K;Fukushi I;Okada Y
据推测，背髓质中的孤束核（NTS）包括对中枢神经系统中的高碳酸血症或缺氧做出反应的气体传感器细胞。在本研究中，我们分析了体外新生大鼠 NTS 区域对高碳酸血症和缺氧的细胞反应。从新生大鼠（P0-P4）中分离出脑干和脊髓，并在头端区后部水平横向切开。为了检测细胞反应，将钙指示剂俄勒冈绿压力注射到髓质尾侧或头侧块切面下方的 NTS 中，并在制备物中注入人工脑脊液 (25–26°C)。我们首先检查了细胞对高碳酸刺激（从 2% CO2 到 8% CO2）的反应，然后检查了对低氧刺激（从 95% O2 到 5% CO2 到 0% O2）的反应。我们在标准溶液和两种不同的突触阻断溶液中测试了这些反应：(1) 鸡尾酒阻断剂溶液，包括荷包牡丹碱、马钱子碱、NBQX 和 MK-801 或 (2) TTX 溶液。实验结束时，将过液钾浓度从 3 mM 降低至 0.2，将记录的细胞分类为神经元和星形胶质细胞。使用共焦钙成像系统检测细胞的激发作为荧光强度的变化。在突触阻断溶液（鸡尾酒或 TTX 溶液）中，7.6% 和 8% 的 NTS 细胞分别对高碳酸和低氧刺激做出反应，其中大约 2% 对两种刺激都有反应。其中一些细胞对低K+有反应，它们被分类为星形胶质细胞，其中包括43%的高碳酸血症敏感细胞、56%的缺氧敏感细胞和54%的两种刺激敏感细胞。值得注意的是，通过低 K+ 刺激鉴定出的推定星形胶质细胞中有 49% 对高碳酸血症、缺氧或两者均敏感。在存在神经胶质细胞优先阻断剂 5 mM 氟乙酸盐（加上 0.5 μM TTX）的情况下，与所有其他条件相比，缺氧敏感细胞的百分比显着降低。这是首次揭示NTS包含高碳酸血症和缺氧双重敏感细胞的研究。这些结果表明 NTS 区域的星形胶质细胞可以充当中央气体传感器。
It is supposed that the nucleus of the solitary tract (NTS) in the dorsal medulla includes gas sensor cells responsive to hypercapnia or hypoxia in the central nervous system. In the present study, we analyzed cellular responses to hypercapnia and hypoxia in the NTS region of newborn rat in vitro preparation. The brainstem and spinal cord were isolated from newborn rat (P0-P4) and were transversely cut at the level of the rostral area postrema. To detect cellular responses, calcium indicator Oregon Green was pressure-injected into the NTS just beneath the cut surface of either the caudal or rostral block of the medulla, and the preparation was superfused with artificial cerebrospinal fluid (25–26°C). We examined cellular responses initially to hypercapnic stimulation (to 8% CO2 from 2% CO2) and then to hypoxic stimulation (to 0% O2 from 95% O2 at 5% CO2). We tested these responses in standard solution and in two different synapse blockade solutions: (1) cocktail blockers solution including bicuculline, strychnine, NBQX and MK-801 or (2) TTX solution. At the end of the experiments, the superfusate potassium concentration was lowered to 0.2 from 3 mM to classify recorded cells into neurons and astrocytes. Excitation of cells was detected as changes of fluorescence intensity with a confocal calcium imaging system. In the synaptic blockade solutions (cocktail or TTX solution), 7.6 and 8% of the NTS cells responded to hypercapnic and hypoxic stimulation, respectively, and approximately 2% of them responded to both stimulations. Some of these cells responded to low K+, and they were classified into astrocytes comprising 43% hypercapnia-sensitive cells, 56% hypoxia-sensitive cells and 54% of both stimulation-sensitive cells. Of note, 49% of the putative astrocytes identified by low K+ stimulation were sensitive to hypercapnia, hypoxia or both. In the presence of a glia preferential blocker, 5 mM fluoroacetate (plus 0.5 μM TTX), the percentage of hypoxia-sensitive cells was significantly reduced compared to those of all other conditions. This is the first study to reveal that the NTS includes hypercapnia and hypoxia dual-sensitive cells. These results suggest that astrocytes in the NTS region could act as a central gas sensor.
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DOI：
10.1016/s0034-5687(01)00284-5
发表时间：
2001-12-01
期刊：
RESPIRATION PHYSIOLOGY
影响因子：
--
作者：
Dean, JB;Kinkade, EA;Putnam, RW
通讯作者：
Putnam, RW
影响因子：
4
作者：
Haertel, Kai;Singaravelu, Karthika;Deitmer, Joachim W.
通讯作者：
Deitmer, Joachim W.
DOI：
10.1126/science.1190721
发表时间：
2010-07-30
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Gourine AV;Kasymov V;Marina N;Tang F;Figueiredo MF;Lane S;Teschemacher AG;Spyer KM;Deisseroth K;Kasparov S
通讯作者：
Kasparov S
影响因子：
5.9
作者：
Chebbo, Ahmad;Tfaili, Amer;Jones, Shirley F.
通讯作者：
Jones, Shirley F.
影响因子：
2.9
作者：
Costa, Kaue M.;Moraes, Davi J. A.;Machado, Benedito H.
通讯作者：
Machado, Benedito H.