Focal CO2 dialysis in raphe obscurus does not stimulate ventilation but enhances the response to focal CO2 dialysis in the retrotrapezoid nucleus
Focal CO2 dialysis in raphe obscurus does not stimulate ventilation but enhances the response to focal CO2 dialysis in the retrotrapezoid nucleus
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DOI：
10.1152/japplphysiol.00120.2008
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发表时间：
2008-07-01
影响因子：
3.3
通讯作者：
Nattie, Eugene
中科院分区：
文献类型：
--
作者：
Dias, Mirela Barros;Li, Aihua;Nattie, Eugene
同时抑制后斜方核（RTN）和中缝隐核（ROb）可使全身CO2反应降低51%，其效果大于单独抑制RTN（-24%）或ROb（0%），表明ROb通过与RTN相互作用调节化学感受（19）。我们进一步研究了这种相互作用，同时透析的人工脑脊液平衡与25%CO2在两个探头位于或邻近的RTN和ROB在清醒的成年雄性大鼠。在30 ℃下用全身体积描记器测量通气量.有四组（n = 5）：1）探针正确放置在RTN和ROb（RTN-ROb）中; 2）一个探针正确放置在RTN中，一个探针不正确放置在ROb附近的区域（RTN-ROb-ROb）; 3）一个探针正确放置在ROb中，一个探针不正确放置在RTN附近的区域（peri-RTN-ROb）;和4）两个探针都没有正确放置（peri-RTN-peri-ROb）。与基线相比，RTN-ROb的局灶性同时酸化显著增加通气量（（V）超过点E）高达22%，呼吸频率和潮气量均显著增加。RTN-R-ROb的局灶性酸化与基线相比，在点E上显著增加（V）高达15%。ROb和peri-RTN的局灶性酸化没有显著影响。RTN和ROb外部区域的同时酸化实际上比点E降低了（V）高达11%。这些结果支持ROb在RTN的中枢化学感受方面的调节作用。
Simultaneous inhibition of the retrotrapezoid nucleus (RTN) and raphe obscurus (ROb) decreased the systemic CO2 response by 51%, an effect greater than inhibition of RTN (- 24%) or ROb (0%) alone, suggesting that ROb modulates chemoreception by interaction with the RTN (19). We investigated this interaction further by simultaneous dialysis of artificial cerebrospinal fluid equilibrated with 25% CO2 in two probes located in or adjacent to the RTN and ROb in conscious adult male rats. Ventilation was measured in a whole body plethysmograph at 30 C. There were four groups (n = 5): 1) probes correctly placed in both RTN and ROb (RTN-ROb); 2) one probe correctly placed in RTN and one incorrectly placed in areas adjacent to ROb (RTN-peri-ROb); 3) one probe correctly placed in ROb and one probe incorrectly placed in areas adjacent to RTN (peri-RTN-ROb); and 4) neither probe correctly placed (peri-RTN-peri-ROb). Focal simultaneous acidification of RTN-ROb significantly increased ventilation ((V) over dot E) up to 22% compared with baseline, with significant increases in both breathing frequency and tidal volume. Focal acidification of RTN-peri-ROb increased (V) over dot E significantly by up to 15% compared with baseline. Focal acidification of ROb and peri-RTN had no significant effect. The simultaneous acidification of regions just outside the RTN and ROb actually decreased (V) over dot E by up to 11%. These results support a modulatory role for the ROb with respect to central chemoreception at the RTN.