Skip to main content
. 2000 Feb;129(4):782–790. doi: 10.1038/sj.bjp.0703090

Figure 3.

Figure 3

Rat colon: (a) Schematic arrangement of the NANC neurone/pacemaker/smooth muscle system and the proposed sites of action of agonists for IP1, EP3, nicotinic (N) and β3-adrenergic receptors. β3-Adrenoceptors may also be located on the smooth muscle cell. NOS=nitric oxide synthase; X=unknown, apamin-sensitive transmitter. The pacemaker and smooth muscle cells are coupled by gap junctions. TTX inhibits the action of cicaprost and nicotine by abolishing action potential conduction in NANC neurones. (b) Typical effects on spontaneous motility of cicaprost and nicotine after 50 min exposure to BMY 45778. (c) Effects of carbacyclin, sulprostone and ONO-AP-324 in the presence of 1 μM TTX.