Effects of a glucocorticoid on development of kidney deficiency syndrome in a rat model of asthma

Abstract

To observe the effects of dexamethasone (DXM) on changes of syndrome and hypothalamic-pituitary-adrenal (HPA) axis of asthmatic rats at different stages of intervention (before withdrawal, during withdrawal and after withdrawal). Asthma was induced in rats by inhalation of 1% ovalbumin. Rats in DXM group were treated with different concentrations of DXM by intra-abdominal injection. At the different stages of DXM treatment (before withdrawal, during withdrawal and after withdrawal), symptoms of the rats were observed to differentiate the syndromes according to yin-deficiency and yang-deficiency measurement standard. Content of serum corticosterone (CORT) was detected by enzyme-linked immunosorbent assay, and contents of plasma adrenocorticotropic hormone (ACTH) and bone Gla-protein (BGP), and content of corticotropin-releasing hormone (CRH) in hypothalamic homogenate were detected by radioimmunoassay. Rats in the DXM group were differentiated as yin-deficiency syndrome before the stage of hormone withdrawal. During the period of hormone withdrawal and after the withdrawal, syndromes of rats in the DXM group accorded with the standards of yin- and yang-deficiency. During the period of treatment with DXM, contents of CORT, ACTH and CRH were significantly decreased, but recovered after DXM withdrawal. BGP level in the DXM group was lower than those in the normal group and the model group during all the stages. Asthmatic rats treated with DXM have different syndrome characteristics in different stages. Kidney deficiency will be caused by DXM treatment.