Fig. 2.

Log concentration–response relaxation curves to 5′-N-ethylcarboxamidoadenosine (NECA), in the absence (open circle) and presence (closed circle) of 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 0.1 μM) (a), 4-(-[7-amino-2-(2-furyl)[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl) phenol (ZM241385, 0.1 μM) (b), 4-(2,3,6,7-tetrahydro-2,6-dioxo-1-propyl-1H-purin-8-yl)-benzenesulfonic acid potassium salt (PSB1115, 0.1 μM) (c) or N-[9-chloro-2-(2-furanyl)[1,2,4]-triazolo[1,5-c]quinazolin-5-yl]benzene acetamide (MRS1220, 10 μM) (d), on 1 μM noradrenaline (NA)-precontracted pig prostatic small arteries. Results are expressed as a percentage of the NA-induced contraction and represent mean ± s.e.m. of six to eight arteries. *P < 0.05 versus control value (paired t test)