Ion Channel Effects Essay -- Medicine Drugs Prozac Pharmacy Essays

Ion Channel Effects The drug Prozac, otherwise known as Fluoxetine, has been believed to cause few side effects in general. Evidence also indicates that fluoxetine has various additional effects on several ion channels within the brain. Fluoxetine has demonstrated exerted effects on a variety of ion channels, the drug inhibited K+ and Na+ currents in lens and corneal epithelium, and the inhibitory effects of fluoxetine on ionic currents (Hahn, 1999). This suggests that since local concentration of fluoxetine may rise in the small extracellular space surrounding neurons, fluoxetine could act as an ion channel inhibitor in the brain. Research done by the Department of Physiology, College of Medicine, at the Catholic University of Korea, showed that fluoxetine is a potent inhibitor of voltage activated K+, Ca2+, and Na+ channels in PC12 cells. The inhibition of K+ channels by fluoxetine was concentration dependent but was not voltage dependent (Hahn, 1999). The inhibitory effects of fluoxetine on K+ currents were not abolished by inhibitors of protein kinases (H7, staurosporine, Rp cAMPS), indicating that protein kinases and G proteins were not involved in the inhibition of K+ currents by fluoxetine (Hahn, 1999). The study concluded that the overall effects of fluoxetine on neurons will be determined by the expression pattern of individual ion channels in different neurons, and this phenomenon may have pharmacological implications (Hahn, 1999). Norfluoxetine is the most important active metabolite of the antidepressant compound, flouxetine. In a study done by the University Medical School of Debrecen, the effects of fluoxetine and its major metabolite, norfluoxet... ...Glenmullen, Joseph, PhD. Prozac Backlash, 2001 Greens Fortuna Pharmacy, patient information leaflet, (2005) Hahn, J., The effects of Prozac on the Brain, (1999) Kalat, James W., Biological Psychology, 8th ed., (2004) Kobayashi, Toru, Kazuo, Washiyama, Kazutaku, Ikeda, Inhibitin of G protein-activated inwardly rectifying K+ channels by fluoxetin(Prozac), British Journal of Pharmacology,(2003), 138, 1119-1128. Magyar J, Swentandrassy N, Banyasz T, Kecskemeti V, and Nanasi PP, Department of Physiology, University Medical School of Debrecen, Hungary, (2004) Turking, Carol Ann, and Kaplan, Eliot F.,M.D., Making the Prozac Decision, (1994) Twersky, Ori. FDA Approves Prozac for Treating Severe form of PMS, WebMD, Medical News, (2000) Walker, P.W. Cole, J.O., and Gardner E.A. , Improvement in Fluoxetine-associated dysfunctions, (1993)