Acetylcholine (ACh) was found to enhance the uptake of radioactive glucose into C2C12 cells, and this effect was suppressed by muscarinic M1 receptor activation. Pharmacological inhibition of phospholipase C also had an effect on ACh's action in C2C12 cells. Additionally, the data suggests that the activation of M1 and/or M4 receptors may have potential for reducing symptoms of schizophrenia. ACh's effects on the hippocampus suggest that M1 receptor activation could have a therapeutic potential for neurodegenerative diseases. Studies also show that both classical and atypical agonists activate M1 receptors through the same molecular switch. Atropine and pirenzepine, muscarinic receptor antagonists, were also found to have an effect on ACh's action, suggesting a possible role in regulating GLP-1 secretion.