牵拉猫左心房所致的肾效应

RENAL RESPONSES TO LEFT ATRIAL STRETCH IN THE CAT

本实验在50只麻醉猫中研究了牵拉左心房(LAS)对尿量(UV)、尿钠(U_(Na)V)和尿钾(U_KV)排出量的影响。在迷走神经完整的动物,LAS 导致 UV,U_(Na)V 和 U_KV(P<0.001)明显增加。切断迷走神经后 LAS 仍能使 UV,U_(Na)V 有所增加(p<0.01),但增加量明显低于迷走神经完整的动物(P<0.005)。在迷走神经完整的猫滴注肝素(10U/min/mg)后,LAS 也能引起 UV,U_(Na)V 和 U_KV 的增加,但增值明显低于没有滴注肝素的猫。在迷走神经切除后滴入肝素,则 LAS 的肾效应消失(p>0.05)。切断左侧肾神经后,LAS 引起神经完整肾尿量和尿钠排出显著增加(P<0.001)。而去神经肾对 LAS 的效应虽减弱,但其增值仍有显著性。两侧肾效应的差异,在统计学上是显著的(P<0.05)。上述结果说明,LAS 在麻醉猫中能引起尿量,尿钠和尿钾明显增加,这些效应是神经反射和体液机制共同作用的结果。

The effects of left atrial stretch(LAS)on urine volume(UV),urinary sodiumexcretion(U_(Na)V)and potassium excretion(U_kV)were studied in 50 anesthetizedcats.LAS resulted in a marked increase in UV,U_(Na)V and U_kV(all P<0.001)in the intact animals.Although LAS still caused an increase in UV and U_(Na)V(P<0.01)after vagotomy,the increments were significantly less than those in vagiintact animals(P<0.005).LAS also induced an increase in UV,U_(Na)V and U_kV(P<0.05)in the vagi intact cats with heparin infusion(10U/min/kg),but the in-crements were significantly less than those in the cats without heparin(P<0.05).The responses to LAS were abolished by infusion of heparin after vagotomy(P>0.05).Following left renal denervation,the responses to LAS remained unchan-ged in the innervated kidney,while those in denervated kidney were attenuated,though still significant.The difference in the response between the innervatedand the denervated kidneys was statistically significant(P<0.05).These resultsindicate that LAS can induce a marked increase in UV,U_(Na)V and U_kV in anes-thetized cats through both neural and humoral mechanisms.