Interrenal Function in Larval Ambystoma tigrinum. III. Acid-Base Balance Responses

• Published in: General and comparative endocrinology Vol. 90; no. 1; pp. 100 - 108
• Main Authors: Aguiniga, Elsa M., Stiffler, Daniel F.
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.04.1993; Elsevier
• Subjects: Acid-Base Equilibrium - drug effects; Acid-Base Equilibrium - physiology; Acidosis, Respiratory - etiology; Acidosis, Respiratory - physiopathology; Aldosterone - blood; Aldosterone - pharmacology; Aldosterone - physiology; Ambystoma - blood; Ambystoma - physiology; Ambystoma tigrinum; Aminoglutethimide - pharmacology; Animals; Biological and medical sciences; Blood gas. Hemoglobin. Myoglobin. Hemotissulary gas exchange. Acid-base balance; Fundamental and applied biological sciences. Psychology; Hypercapnia - physiopathology; Larva - drug effects; Larva - physiology; Reference Values; Sodium Radioisotopes; Vertebrates: respiratory system; Acid base balance; Vertebrata; Larva; Steroid hormone; Corticosterone; Caudata; Amphibia; Ambystoma tigrinum; Respiratory acidosis; Aldosterone; Interrenal
• ISSN: 0016-6480; 1095-6840
• DOI: 10.1006/gcen.1993.1064

Larval Ambystoma tigrinum (59-199 g) were treated with the drug aminoglutethimide (6 mg/day) in order to abolish steroid hormone synthesis. Steroid deprivation prevented the increase in plasma aldosterone concentration observed in sham-infused larvae during respiratory acidosis. It also blocked the normal compensatory response to respiratory acidosis of elevated plasma [HCO3-] and inhibited cutaneous Na+ transport. Aldosterone (10 μg/day) and, to a lesser extent, corticosterone (240 μg/day) restored the compensatory response. Aldosterone replacement also stimulated cutaneous Na+ transport in AG-inhibited larvae. The results suggest that aldosterone, at about 1000 pg/ml, supports the compensatory ionic responses to respiratory acidosis in this species.