Comparative Study on Characteristic Chromatogram and Antipyretic Effects of Fresh and Raw Rehmanniae Radix Formula Granules

OBJECTIVE  To compare the characteristic chromatograms and antipyretic effects between fresh and raw Rehmanniae Radix formula granules.

METHODS  Collected the characteristic chromatograms of 3 batches of fresh Rehmanniae Radix formula granules and 9 batches of raw Rehmanniae Radix formula granules by using UPLC. Compared the differences of characteristic chromatograms of iridoid glycosides and phenylethanol glycosides in fresh and raw Rehmanniae Radix formula granules. Seventy SPF-grade SD rats were randomly divided into 7 groups based on their basal body temperature, namely, normal control group, model control group, ibuprofen group, high dose group of raw Rehmanniae Radix formula granules, low dose group of raw Rehmanniae Radix formula granules, high dose group of fresh Rehmanniae Radix formula granules, and low dose group of fresh Rehmanniae Radix formula granules. Except for the normal control group, all other groups were injected intraperitoneally with 100 μg·kg⁻¹ lipopolysaccharide(LPS), while the normal control group was injected intraperitoneally with an equal volume of physiological saline. Measured the body temperature every 2 h, calculated the temperature changes and inhibition rate of temperature rise at each monitoring point.

RESULTS  Compared with the characteristic chromatograms of fresh Rehmanniae Radix formula granules, the peak 8 in the characteristic chromatogram of iridoid glycosides in raw Rehmanniae Radix formula granules was missing, and the characteristic chromatogram of phenylethanol glycosides had an additional peak 9. These two characteristic peaks could be used for the exclusive identification of fresh and raw Rehmanniae Radix formula granules. Injected the LPS for 2, 4 and 6 h later, the high dose fresh Rehmanniae Radix formula granules of group had a significant antipyretic effect(P<0.05 or P<0.01). The inhibition rate of temperature rise in rats with each formula granule sample was compared as follows: high dose of fresh Rehmanniae Radix formula granules>high dose of raw Rehmanniae Radix formula granules>low dose of fresh Rehmanniae Radix formula granules>low dose of raw Rehmanniae Radix formula granules. The antipyretic effect of fresh Rehmanniae Radix formula granules on LPS induced fever model in rats was better.

CONCLUSION  There are differences in the characteristic chromatograms and antipyretic effects of fresh and raw Rehmanniae Radix formula granules, and the antipyretic effect of fresh Rehmanniae Radix formula granules was better. The research results can provide data support for the clinical promotion of fresh Rehmanniae Radix formula granules.