ABSTRACT
Acid-sensing ion channels are a class of extracellular H+ activated cation channels, belonging to the amiloride-sensitive epithelial Na+ channel/degenerin (ENaC/DEG) superfamily. During extracellular acidification, the channels are activated and produce corresponding action potential. Acid-sensing ion channels are extensively expressed in the peripheral and central nervous system. It plays an important in synaptic plasticity, mechanical sensation, injury sensation related to acidosis of local tissues, acid reception and retinal regulation. This article reviews the expression, biological characteristics and functions of acid-sensing ion channels in cochlea, vestibular tissue and auditory center, so as to improve the understanding of physiology and pathophysiology of auditory system.
ABSTRACT
Multiple acyl-CoA dehydrogenase deficiency (MADD) is a common inborn error of fatty-acid metabolism characterized by vomiting, acidosis and lipid storage myopathy, and the clinical manifestations of MADD are highly heterogeneous. MADD can be diagnosed by the elevation of multiple acyl-carnitine in blood and glutaric acid or other organic acid in urine. The neonatal-onset patients have severe symptoms and poor prognosis. However, oral riboflavin supplementation (can completely rescue) ameliorate the clinical and laboratory disorders rapidly especially to the riboflavin responsive MADD. Additionally, patients not sensitive to riboflavin should also take low lipid, low protein and high carbonhydrate diet besides riboflavin.
ABSTRACT
Citrin deficiency is an autosomal recessive disorder caused by mutations of the SLC25A13 gene.As a calcium binding mitochondrial aspartate glutamate carrier,Citrin plays an important role not only in the urea synthesis but NADH shuttle as well.Citrin deficiency has two phenotypes:adult-onset typeⅡcitrullinemia and neonatal intrahepatic cholestasis.Citrin deficiency is a common congenital metabolic defect first found in Japan and now is considered as a global disease.