codeine , a weak opiate ligand , was also ineffective as were the kappa-opioid agonist ketocyclazocine and the sigma-opioid agonist phencyclidine . the hyperthermia which accompanies peripheral and central injections of morphine was not observed after hypothalamic application of a quantity of levorphanol sufficient to stimulate feeding .
C0009214
codeine
C0026549
morphine