[Experimental research on treatment of acute organophosphorus insecticides poisoning with high-dose atropine: upregulation of muscarinic receptor].

Acute organophosphorus insecticides poisoning (AOIP) is a common medical emergency. There is, at present, a tendency to use high-dose atropine treatment (HDAT). This study aims to test if, during AOIP, HDAT would cause upregulation of muscarinic receptor (M-R). Male mice of the same batch and strain were raised, randomly divided into 3 groups and orally fed with DDVP of the same dose. HDAT for 7 days was given to group A, HDAT for 36 hours was given to group B and low-dose atropine treatment for 36 hours was given to group C. Then radionuclide assay was employed to measure the M-R in the brain and atrium of the mice in each group. The results were that, compared with a control group, the Bmax values (fmol.mg protein-1) of M-R in groups A and B were increased significantly (P < 0.01), while that in group C showed no evident change (P > 0.05). These results indicate that HDAT leads to some physiological change in the body, which may be responsible for the development of poisoning rebound and atropine dependence.