Figure 1.
Mean contractile response of lateral saphenous vein to increasing concentrations of 5-hydroxytryptamine (5HT) receptor agonists: (A) CP 93129, a selective agonist for receptor 5HT1B; (B) L-694,247, a selective agonist for receptor 5HT1D; (C) TCB2 a selective agonist for receptor 5HT2A; (D) ergovaline, an ergot alkaloid obtained from a tall fescue seed extract. Veins were biopsied from steers following an 87- to 101-d grazing period on a bermudagrass pasture (n = 5), Kentucky-31 (KY31) toxic endophyte-infected tall fescue pastures not treated (n = 5), or treated with aminopyralid and metsulfuran-methyl (Chaparral; n = 5) to suppress seedhead production.