Autoradiographic changes of3H‐α‐bungarotoxin binding in rat hind limb muscles after a cryoinjury of the sciatic nerve and in acrylamide intoxication

Abstract
The morphological distribution of acetylcholine receptors in rat tibialis anterior and soleus muscles after a cryoinjury of the sciatic nerve was studied byin vitroautoradiography with3H‐α‐bungarotoxin (3H‐α‐Btx). Tibialis anterior from rats intoxicated with acrylamide was also investigated by this technique. A computer system was used for densitometry and colour coding of the autoradiographs. In normal muscle,3H‐α‐Btx binding was observed only at the motor endplates. From the second day after the nerve lesion the area of binding spread from the motor endplate region towards the muscle‐tendon regions and on the 16th day almost all parts of the muscles showed increased binding. The binding had begun to decrease in the middle parts of the muscles on the 20th day and on the 30th day binding was observed only in the motor endplate area. Tibialis anterior from rats intoxicated with acrylamide (total dose 1100 mg·kg‐1) showed3H‐α‐Btx binding over the entire muscle.