Figure 8.

Examples of Ca²⁺-activated K⁺ current (I_K-Ca) evoked by muscarinic agonists. (a – g) Current responses of different cells to (a) carbachol, (b) acetylcholine (ACh), (c) oxotremoline-M (Oxo-M), (d) arecoline (Are), (e) bethanechol (BCh), (f) pilocarpine (Pilo) and (g) McN-A343 applied at a maximally effective concentration (300 or 1000 μM) and subsequent application of 10 mM caffeine as indicated by the lines. The cells were held at 0 mV, a level close to the reversal potential for I_cat and exposed to the drugs 5 min after establishment of whole-cell recording mode. Mean values for the amplitudes of agonist-evoked I_K-Ca, subsequent caffeine-evoked I_K-Ca and the sum of both currents are given in Table 2.