Detect Of The Anti-m Muscarinic Receptor Autoantibody Hypotype In Rats With Cor Pulmonale And Study Of The Biological Effects

Objective: To detect the diversity of anti-m3 muscarinic receptor autoantibody from the sera between healthy rats and cor pulmonale model rats before and after treatment . Moreover the functional effects of the purified anti-m2 muscarinic receptor autoantibodies on isolated tracheal smooth muscle in healthy rats were also observed. Clarify the correlation of the production of the anti-m2/m3 muscarinic receptor autoantibody to the development of cor pulmonale.Methords: The rats without the autoantibodies against the second extracellular loop of rat m3-receptor were chosen to establish models of cor pulmonale, also the control group were established. The mean pulmonary arterial pressure were measured and (right ventricular/left ventricular+interventricular septum) were weighed after treatment. The anti-m3 muscarinic receptor autoantibody were assessed with SA-ELLISA immunoassay at 1,2,3,4,5 weeks after treatment in both groups. Attach tonotransducer with isolated annulus trachea of rats, observe the contractility of tracheal smooth muscle when added with purified anti-m2 muscarinic receptor autoantibodies.Result: (1) 5 weeks after treatment the mean pulmonary arterial pressure 30.3±2.9mmHg and the weight of right ventricular/left ventricular+interventricular septum 34.5±4.8% were obviously higher than the control group 17.4±3.2mmHg,28.7±4.6% ( P<0.05 ). (2) In the model group, anti-m3 muscarinic receptor autoantibodies were detected at 1 week after treatment and reached to it′s peak at 2 weeks (positive rate 41.6%,mean titer 1:65.5+3.7 ) which was obviously higher than the control group, then decreased gradually.(3)The anti-m2 muscarinic receptor autoantibody doesn't have direct action to isolated annulus trachea of rats. Add anti-m2 muscarinic receptor autoantibodies when the annulus trachea contracted to its platform stage by using acetylcholine , then the contraction amplitude of annulus trachea can be increased from 2.51±0.25g to 2.93±0.36g(P<0.05)。Conclusion: (1)The positive ratio of anti-m3 muscarinic receptor autoantibodies and antibody titer were much higher than that from the health subject in rat chronic cor pulmonale(2)When anti-m2 muscarinic receptor autoantibody used on isolated annulus tracheal smooth muscle of rats, it can enhance the contractility of annulus tracheal smooth muscle by acting on acetylcholine.(3)Two antibody take effect in form of chronic cor pulmonale and indicates that the immuno-factors may play a important role in the pathogenisis of chronic cor pulmonale.