A muscarine-resistant M-current in C cells of bullfrog sympathetic ganglia.

C cells of bullfrog sympathetic ganglia have an M-current similar to that of the larger B cells. However, the M-current of C cells is much less sensitive to muscarinic agonists. The M-current of C cells is blocked by barium and by LHRH (mammalian luteinizing hormone-releasing hormone). LHRH sometimes also decreases a different conductance, with an extrapolated reversal potential near 0 mV. These results demonstrate that the coupling of receptors to ion channels can vary between cell types, even within a single ganglion.