暴露于水滴定碱度和氯化钠浓度变化的小龙虾细胞外pH值的通气调节

Ventilatory regulation of extracellular pH in crayfish exposed to changes in water titration alkalinity and NaCl concentration.

作者信息

Burtin B, Massabuau J C, Dejours P

出版信息

Respir Physiol. 1986 Aug;65(2):235-43. doi: 10.1016/0034-5687(86)90053-8.

Abstract

The mechanisms of extracellular pH regulation were studied in normoxic crayfish Astacus leptodactylus during changes in water ionic composition at 13 degrees C. In artificial waters all ambient physico-chemical properties were controlled. Ventilatory changes and the time course of hemolymph acid-base balance, ABB, were followed after a decrease of water titration alkalinity, TAw, from 4 to 2 meq X L-1 simultaneously associated with either an increase of NaCl concentration, [NaCl]w, from 0.5 to 5 mmol X L-1, or a decrease of [NaCl]w, from 0.5 to 0.15 mmol X L-1. The ABB changes were characterized by a hypercapnic acidosis attributable to the decrease of TAw. Depending on the simultaneous change of [NaCl]w, two different mechanisms of compensation were observed. When [NaCl]w increased, the compensation was metabolic: the ventilatory requirement, VW X MO2-1, did not vary. When [NaCl]w decreased, the compensation was ventilatory: VW X MO2-1 doubled. It is concluded that in water-breathers ventilation, contrary to what is generally accepted, can play a role in extracellular ABB regulation.

摘要

在13摄氏度下，研究了常氧条件下细指螯虾（Astacus leptodactylus）在水体离子组成变化时细胞外pH调节的机制。在人工水体中，所有环境理化性质均受到控制。在水的滴定碱度（TAw）从4 meq X L-1降至2 meq X L-1的同时，要么将NaCl浓度（[NaCl]w）从0.5 mmol X L-1提高到5 mmol X L-1，要么将[NaCl]w从0.5 mmol X L-1降低到0.15 mmol X L-1，随后跟踪通气变化以及血淋巴酸碱平衡（ABB）的时间进程。ABB变化的特征是由于TAw降低导致的高碳酸血症性酸中毒。根据[NaCl]w的同时变化，观察到两种不同的代偿机制。当[NaCl]w增加时，代偿是代谢性的：通气需求（VW X MO2-1）没有变化。当[NaCl]w降低时，代偿是通气性的：VW X MO2-1增加了一倍。得出的结论是，在水生呼吸动物中，与普遍观点相反，通气在细胞外ABB调节中可以发挥作用。