Kopp U, DiBona G F
Am J Physiol. 1983 Apr;244(4):F418-24. doi: 10.1152/ajprenal.1983.244.4.F418.
Anesthetized dogs with isolated carotid sinus preparation were used to examine the mechanisms involved in the increase in renin secretion rate produced by carotid baroreceptor reflex renal nerve stimulation (RNS) at constant renal perfusion pressure. Lowering carotid sinus pressure by 41 +/- 5 mmHg for 10 min increased mean arterial pressure and heart rate, caused no or minimal renal hemodynamic changes, decreased urinary sodium excretion, and increased renin secretion rate. Metoprolol, a beta 1-adrenoceptor antagonist, given in the renal artery, did not affect the decrease in urinary sodium excretion but attenuated the increase in renin secretion rate, from 1,764 +/- 525 to 412 +/- 126 ng/min (70 +/- 8%). Indomethacin or meclofenamate, prostaglandin synthesis inhibitors, did not affect the decrease in urinary sodium excretion but attenuated the increase in renin secretion rate, from 1,523 +/- 416 to 866 +/- 413 ng/min (51 +/- 18%). Addition of metoprolol to indomethacin-pretreated dogs attenuated the increase in renin secretion rate from 833 +/- 327 to 94 +/- 60 ng/min (86 +/- 10%). These results indicate that reflex RNS at constant renal perfusion pressure results in an increase in renin secretion rate that is largely mediated by renal beta 1-adrenoceptors and is partly dependent on intact renal prostaglandin synthesis. The beta 1-adrenoceptor-mediated increase in renin secretion rate is independent of and not in series with renal prostaglandins.
采用具有分离颈动脉窦标本的麻醉犬，以研究在恒定肾灌注压下，颈动脉压力感受器反射性肾神经刺激（RNS）引起肾素分泌率增加所涉及的机制。将颈动脉窦压力降低41±5 mmHg持续10分钟，可使平均动脉压和心率升高，未引起或仅引起轻微的肾血流动力学变化，降低尿钠排泄，并增加肾素分泌率。在肾动脉中给予β1肾上腺素能受体拮抗剂美托洛尔，并不影响尿钠排泄的减少，但可减弱肾素分泌率的增加，从1764±525降至412±126 ng/min（70±8%）。前列腺素合成抑制剂吲哚美辛或甲氯芬那酸，并不影响尿钠排泄的减少，但可减弱肾素分泌率的增加，从1523±416降至866±413 ng/min（51±18%）。在吲哚美辛预处理的犬中加入美托洛尔，可使肾素分泌率的增加从833±327降至94±60 ng/min（86±10%）。这些结果表明，在恒定肾灌注压下的反射性RNS导致肾素分泌率增加，这在很大程度上由肾β1肾上腺素能受体介导，并且部分依赖于完整的肾前列腺素合成。β1肾上腺素能受体介导的肾素分泌率增加独立于肾前列腺素，且与肾前列腺素无串联关系。
