Experimental Study Of Anti-acid Therapy For Idiopathic Pulmonary Fibrosis Combined With Gastric Acid Aspiration

Objective:To explore the effect of acid inhibition therapy on the development and prognosis of idiopathic pulmonary fibrosis in rats with acid misinhalation.Methods:Thirty-six SD male rats were randomly divided into normal control group(10 rats),model group(6 rats),acid suppression group(10 rats)and glucocorticoid group(10 rats).The pulmonary fibrosis model was established by intranasal drip of bleomycin(7ug/g)in model group,acid suppression group and glucocorticoid group,while the control group was intranasally dripped with normal saline.After 28 days of modeling,acid misinhalation model was established by inhaling dilute hydrochloric acid by atomization in acid inhibition group and glucocorticoid group.Ranitidine hydrochloride and prednisone acetate were given intragastrically for 28 days,while saline aerosol inhalation and intragastric administration were given in control group and model group.After 28 days of treatment,pathological changes of lung tissues were observed,arterial partial pressure of oxygen and malondialdehyde(MDA)were measured.Results:1.The lung tissue of the control group was pale pink with clear outline,smooth surface,normal elasticity,no obvious swelling and no bleeding point.In model group,the colour of lungs became darker with naked eyes,some areas were gray-white,the volume of lungs was reduced,the outline of lungs was clear,and the adhesion between lungs and pleura could be seen.In acid-suppressing group and glucocorticoid group,some of the lungs showed signs of repair after 28 days of treatment,which was less severe than that in model group.2.The control group showed normal alveolar structure and no obvious alveolar inflammation.In model group,pulmonary histopathology showed local old hemorrhagic foci,infiltration of macrophages into alveolar cavity,deposition of collagen fibers,proliferation of fibroblasts and degree of pulmonary fibrosis(+++).There was no significant difference in the effective rate between the two groups.The effective rate of the acid suppression group was 67% lower than that of the glucocorticoid group(80%)(p > 0.05).3.The serum MDA [(6.820+0.470)nmol/L] of the control group was lower than that of the model group [(16.040+1.68)nmol/L],the acid-suppressing group[(11.860+2.550)nmol/L] and the glucocorticoid group [(10.310+3.230)nmol/L](p <0.05).The serum MDA levels in acid suppression group and glucocorticoid group were lower than those in model group(p<0.05).There was no significant difference between the acid-suppressing group and the glucocorticoid group(p > 0.05).4.There were no significant differences in [(86.98±7.624)mmHg],model group[(82.80±4.138)mmHg],acid suppression group [(84.375±7.519)mmHg] and glucocorticoid group[(84.375±7.519)mmHg](p > 0.05).Conclusions:To some extent,anti-acid therapy can improve the degree of alveolar inflammation and pulmonary fibrosis in rats with pulmonary fibrosis combined with acid aspiration,and may improve the pulmonary function of rats.