Objective: To investigated the effects of suspended moxibustion stimulating Shenshu (BL23) and Guanyuan (CV4) acupoints on the amygdala and HPA axis in our rat model and elucidated the possible molecular mechanisms of moxibustion on kidney- deficiency symptom pattern (KYDS).
Methods: Sixty male Sprague Dawley rats were randomly divided into a control group ( 12) and an experimental group ( 48). Rats in the experimental group were given intramuscular injections of hydrocortisone to establish a KYDS model. The 48 rats successfully modeled were then randomly divided into a model group (model, 12), a carbenoxolone intraperitoneal injection group (CBX, 12), a moxibustion group (moxi, 12), and a moxi + CBX group ( 12). In the moxi, the Shenshu (BL23) and Guanyuan (CV 4) acupoints were treated with moxibustion for 14 d. After treatment, measures were taken of serum levels of corticosterone (CORT), adrenocorticotropic hormone (ACTH), and corticotropin-releasing hormone (CRH). The expression of mineralocorticoid receptors (MRs), glucocorticoid receptors (GRs), 11beta-hydroxysteroid dehydrogenase type 1 (11β-HSD1), CRH, and ACTH in the rats' amygdala, hypothalamus, or pituitary (as appropriate) was detected. Data were analyzed using one-way analysis of variance.
Results: Compared with those of the control group, the serum levels of CRH, ACTH, and CORT; the mRNA and protein expressions of MR, GR, and 11β-HSD1 in the amygdala; the mRNA and protein expressions of 11β-HSD1 in the hypothalamus; the CRH mRNA expression in the amygdala and hypothalamus; and the ACTH mRNA expression in the pituitary of the rats in the model group were all significantly decreased (0.05 or 0.01). After treatment with moxibustion, all the aforementioned observation indices except for 11β-HSD1 mRNA expression were ameliorated compared with those in the model group (0.05 or 0.01).
Conclusions: Suspended moxibustion can effectively improve the serum levels of ACTH, CRH, and CORT and can up-regulate the mRNA and protein expressions of MR, GR, 11β-HSD1, CRH, and ACTH in the amygdala and hypothalamus of KYDS rats. This may be one of the molecular mechanisms with which moxibustion alleviates KYDS.
Keywords: 11-beta-hydroxysteroid dehydrogenase type 1; amygdala; hypothalamus; kidney- deficiency; moxibustion; receptors, glucocorticoid; receptors, mineralocorticoid.