Koyama S
Am J Physiol. 1984 Oct;247(4 Pt 2):R655-62. doi: 10.1152/ajpregu.1984.247.4.R655.
The time course of changes in mean blood pressure (MBP), heart rate (HR), and renal blood flow (RBF) in a control group of anesthetized dogs given only endotoxin (1 mg/kg iv) was compared with groups pretreated with alpha-antagonists either intravenously or intracisternally (ic). The decreases in MBP and RBF in the control group were abolished by intracisternal prazosin (0.1 mg/kg ic). MBP response to endotoxin after intravenous prazosin did not differ from that of the control group; however, the endotoxin-induced decrease in RBF after intravenous prazosin was significantly greater than that in the control group. HR responses to endotoxin were not altered by either intracisternal or intravenous prazosin. MBP and RBF responses to endotoxin after intravenous or intracisternal yohimbine (0.5 mg/kg iv or ic) did not differ from the control responses. However, significant differences occurred in the time course of changes in HR only when yohimbine was administered intracisternally. These observations suggest that the hypotensive effect and reduction of RBF due to endotoxin may be mediated by alpha 1-adrenoceptors at least in the central nervous system and that of HR response may be mediated alpha 2-adrenoceptors.
将仅给予内毒素（1毫克/千克静脉注射）的麻醉犬对照组的平均血压（MBP）、心率（HR）和肾血流量（RBF）变化的时间过程，与经静脉或脑池内（ic）用α拮抗剂预处理的组进行比较。脑池内给予哌唑嗪（0.1毫克/千克ic）可消除对照组中MBP和RBF的降低。静脉注射哌唑嗪后MBP对内毒素的反应与对照组无差异；然而，静脉注射哌唑嗪后内毒素诱导的RBF降低显著大于对照组。脑池内或静脉注射哌唑嗪均未改变HR对内毒素的反应。静脉或脑池内给予育亨宾（0.5毫克/千克静脉注射或ic）后MBP和RBF对内毒素的反应与对照反应无差异。然而，仅当脑池内给予育亨宾时，HR变化的时间过程才出现显著差异。这些观察结果表明，内毒素引起的低血压效应和RBF降低至少在中枢神经系统中可能由α1肾上腺素能受体介导，而HR反应可能由α2肾上腺素能受体介导。
