4[1]Muller W, Hallermann S, Swandulla D. Opioidergic modulation of voltage-activated K+ currents in magnocellular neurons of the supraoptic nucleus in rat. J Neurophysiol 1999; 81 (4): 1617 - 25
5[2]Prado WA. Involvement of calcium in pain and antinociception. Braz J Med Biol Res 2001; 34(4):449 -61
6[4]Bloomfield SS, Cissell GB, Mitchell J, et al. Analgesic efficacy and potency of two oral controlled-release morphine preparations. Clin Pharmacol Ther 1993; 53(4):469-78
7Stoker DG,,Reber KR,Waltzman LS,et al.Analgesic effi-cacy and safety of morphine-chitosan nasal solution in pati-ents with moderate to severe pain following orthopedic sur-gery. Pain Med . 2008