A comparative study of biological indicators of phlegm-heat syndrome (痰热证) and phlegm-dampness syndrome (痰湿证) model with acute exacerbation of chronic obstructive pulmonary disease

Abstract

Objective To compare phlegm-heat syndrome(痰热证)with phlegm-dampness syndrome(痰湿证)of acute exacerbation of chronic obstructive pulmonary disease(AECOPD)in regard to inflammatory response,hormone level,lung pathological examination and lung function.Methods Fifty-six Wistar rats were randomly divided into four groups,including normal control group,AECOPD group,phlegm-heat syndrome of AECOPD group(PHs group),phlegm-dampness syndrome of AECOPD group(PDs group).The level of white blood cell(WBC)count,neutrophil ratio,free triiodothyronine(FT3),free thyroxine(FT4),epinephrine(E),norepinephrine(NE),cortisol(COR),C-reactive protein(CRP),tumor necrosis factor-α(TNF-α),interleukin-8(IL-8)in blood,and TNF-α,IL-8,intercellular adhesion molecule-1(ICAM-1)in broncho-alveolar lavage fluid(BALF)were determined with radioimmunology.Lung function was tested by whole-body plethysmography.Results ①The count of WBC and neutrophil ratio in PDs group were higher than in PHs group,AECOPD group and normal group,there was significant difference in multiple comparison.The levels of inflammatory mediators in serum and BALF in three model groups were evidently higher than in normal group,and IL-8[(4.13±1.28)μg／L]and CRP((3.07±0.69)μg／L]in serum in PDs group were higher than those in PHs group (1.75±0.53)μg／L,(1.98±0.42)μg／L,both P<0.01].②FT3 level in blood in both AECOPD group and PHs group [(9.44±3.17)pmol／L,(9.95±3.68)pmol／L]was significantly higher than that in normal control group[(4.53±2.80)pmol／L],FT3 in PDs group[(2.13±1.31)pmol／L]was evidently lower than that in normal group(p<0.05 or P<0.01).The level of FT4[(2.23±0.71)pmol／L],E[(87.27±29.32)nmol／L]and NE[(71.69±21.24)nmol／L] in PDs group were all obviously lower than those in normal group[FT4:(4.64±1.49)pmol／L,E:(143.94±32.90)nmol／L,NE:(100.32±27.73)nmol／L,P<0.05 or P<0.01].There was no significant difference in the above three parameters between AECOPD group and normal group.Each parameter in PHs group was markedly higher than that in AECOPD group.The content of COR in PDs group was higher than in PHs group, in which COR was higher than in AECOPD group,which was equal to that in normal group. ③The pathological changes in lung included inflammatory cell infiltration, exfoliation of cilia, dilatation of alveolar spaces of lung tissue in AECOPD group, which were more significant in PHs group and PD group. Inflammatory cells infiltration around the bronchi, thickening of interalveolar spaces, and vasodilatation were more pronounced in PHs group and PDs group than in AECOPD group. Inflammatory cell infiltration around the bronchi were about the same between PHs and PDs groups. ④The levels of peak expiratory velocity (PEV), tidal volume (VT), minute ventilation (MV)were significantly lower in AECOPD group, PHs group and PDs group than in normal control group, but the levels of frequency (f) and inspiratory resistance (Rin) were evidently higher. Compared with AECOPD group, the levels of PEV, VT, MV were significantly decreased, the level of respiratory f and Rin evidently increased in PDs group. Compared with PHs group, the levels of PEV, VT, MV significantly decreased in PDs group, while the level of f and Rin evidently increased. There was no significant difference in the above five parameters between AECOPD group and PHs group. Conclusion The changes in local and systemic inflammatory response, lung histopathological injury in PHs group and PDs group were more evident than changes in AECOPD group. The changes in systemic inflammatory response, decrease in functional indicators of thyroid and adrenal medulla, and decline in lung function were more marked in PDs group than in PHs group. Key words: Chronic obstructive pulmonary disease; Acute exacerbation; Phlegm-heat syndrome; Phlegm-dampness syndrome; Animal model