Fig. 5.

Urine ammonia and C3 expression. Desmopressin has been reported to increase urine ammonia, which has been shown to activate the alternative complement pathway. Consistent with this hypothesis, we found a tendency for an increase in urinary ammonia and renal C3 expression that was primarily identified in proximal tubules [control mice (C) and desmopressin-injected control mice (D)]. Heat stress-exposed mice showed the highest urinary ammonia excretion and renal tubular C3 expression (A, B, and E), whereas heat stress-exposed mice administered desmopressin paradoxically showed a reduction in urinary ammonia and renal C3 deposition (F). *P < 0.05, **P < 0.01, and ***P < 0.001.