[Effect of Lepidium meyenii (Maca) on neurotransmitter level and neuro-endocrine-immune network of deficiency-cold and deficiency-heat syndrome rats].

ABSTRACT

The aim of this paper was to study the effect of Lepidium meyenii(Maca) on cyclic nucleotides, neurotransmitter levels and hypothalamic-pituitary-adrenal axis and immunization of deficiency-cold and deficiency-heat syndrome rats, in order to explore the cold and hot medicinal properties of Maca. SD rats were divided into blank group, deficiency-cold syndrome group, Cinnamomi Cortex of deficiency-cold syndrome(30 g·kg~(-1)) group, high and low-dose Maca groups(2.4, 1.2 g·kg~(-1)), deficiency-heat syndrome group, Phellodendri Chinensis Cortex(PCC) of deficiency-heat syndrome(5 g·kg~(-1)), and high and low-dose Maca groups(2.4, 1.2 g·kg~(-1)). The rats were treated with intramuscular injection of hydrocortisone(20 mg·kg~(-1)) or dexamethasone sodium phosphate(0.35 mg·kg~(-1)) for 21 days to set up the deficiency-cold and deficiency-heat model. The levels of cAMP, cGMP, NE, DA, 5-HT, CRH, ACTH, CORT and IgM, IgG, C3, C4 were detected by radio immunoassay. Both the high-dose Maca group and the low-dose Maca group can significantly improve the overall state and body weight of rats with deficiency-cold syndrome(P<0.01, P<0.05), significantly increasing cAMP, cAMP/cGMP, NE, DA, ACTH(P<0.01, P<0.001), and significantly decreasing 5-HT(P<0.01, P<0.001). However, high-dose and low-dose Maca groups could not improve the deficiency-heat syndrome, and the levels of cAMP, cGMP, cAMP/cGMP, NE, DA, 5-HT and ACTH were not statistically significant. Maca had a significant regulatory effect on CORT, IgM, IgG and C3 content of rats with deficiency-cold and deficiency-heat syndrome(P<0.01, P<0.05, P<0.001). Maca showed the same effect with Cinnamomi Cortex in adjusting the levels of deficiency-cold rats, but in opposition to Phellodendri Chinese Cortex. This paper confirmed that Maca was slightly warm based on its effect on cyclic nucleotide levels and neuro-endocrine-immune networks by the pharmacological experimental method.