References

Anderson, R.J., G.R. Hart, C.P. Crumpler and M.J. Lerman, 1981. Clonidine overdose: Report of 6 cases and review of the literature. Ann. Emerg. Med., 10: 107-112.
PubMed  |  Direct Link  |  

Angelucci, M.E., C. Cesario, R.H. Hiroi, P.L. Rosalen and C. Da Cunha, 2002. Effects of caffeine on learning and memory in rats tested in the Morris water maze. Braz. J. Med. Biol. Res., 35: 1201-1208.
CrossRef  |  PubMed  |  Direct Link  |  

Baldwin, H.A., A.L. Johnston and S.E. File, 1989. Antagonistic effects of caffeine and yohimbine in animal tests of anxiety. Eur. J. Pharmacol., 159: 211-215.
CrossRef  |  PubMed  |  Direct Link  |  

Calev, A., 1994. Neuropsychology and ECT: Past and future research trends. Psychopharmacol. Bull., 30: 461-469.
PubMed  |  Direct Link  |  

Carter, A.J., 1997. Hippocampal noradrenaline release in awake, freely moving rats is regulated by alpha-2 adrenoceptors but not by adenosine receptors. J. Pharmacol. Exp. Ther., 281: 648-654.
PubMed  |  Direct Link  |  

Chamberlain, S.R., U. Muller, A.D. Blackwell, T.W. Robbins and B.J. Sahakian, 2006. Noradrenergic modulation of working memory and emotional memory in humans. Psychopharmacology, 188: 397-407.
CrossRef  |  PubMed  |  Direct Link  |  

Chopin, P., F.C. Colpaert and M. Marien, 2002. Effects of acute and subchronic administration of dexefaroxan, an alpha (2)-adrenoceptor antagonist, on memory performance in young adult and aged rodents. J. Pharmacol. Exp. Ther., 301: 187-196.
PubMed  |  Direct Link  |  

Davis, J.M., Z. Zhao, H.S. Stock, K.A. Mehl, J. Buggy and G.A. Hand, 2003. Central nervous system effects of caffeine and adenosine on fatigue. Am. J. Physiol. Regul. Integr. Comp. Physiol., 284: R399-R404.
CrossRef  |  PubMed  |  Direct Link  |  

Delaney, J., D. Spevack, S. Doddamani and R. Ostfeld, 2006. Clonidine-induced delirium. Int. J. Cardiol., 113: 276-278.
CrossRef  |  PubMed  |  Direct Link  |  

Domino, L.E., S.E. Domino and M.S. Stockstill, 1986. Relationship between plasma concentrations of clonidine and mean arterial pressure during an accidental clonidine overdose. Br. J. Clin. Pharmacol., 21: 71-74.
PubMed  |  Direct Link  |  

Fredholm, B.B., K. Battig, J. Holmen, A. Nehlig and E.E. Zvartau, 1999. Actions of caffeine in the brain with special reference to factors that contribute to its widespread use. Pharmacol. Rev., 51: 83-133.
PubMed  |  Direct Link  |  

Fredholm, B.B., K. Lindstrom and A. Wallman-Johansson, 1994. Propentofylline and other adenosine transport inhibitors increase the efflux of adenosine following electrical or metabolic stimulation of rat hippocampal slices. J. Neurochem., 62: 563-573.
CrossRef  |  PubMed  |  Direct Link  |  

Galeotti, N., A. Bartolini and C. Ghelardini, 2004. Alpha-2 agonist-induced memory impairment is mediated by the alpha-2A-adrenoceptor subtype. Behav. Brain Res., 153: 409-417.
CrossRef  |  PubMed  |  Direct Link  |  

Garrett, B.E. and R.R. Griffiths, 1997. The role of dopamine in the behavioral effects of caffeine in animals and humans. Pharmacol. Biochem. Behav., 57: 533-541.
CrossRef  |  PubMed  |  Direct Link  |  

Grasing, K., M.G. Sturgill, R.C. Rosen, J.R. Trout, T.J. Thomas, G.D. Kulkarni, P. Maines and J.R. Seibold, 1996. Effects of yohimbine on autonomic measures are determined by individual values for area under the concentration-time curve. J. Clin. Pharmacol., 36: 814-822.
PubMed  |  Direct Link  |  

Gulec, S., Y. Aydin, K. Uzuner, B. Yelken and Y. Senturk, 2004. Effects of clonidine pre-treatment on bupivacaine and ropivacaine cardiotoxicity in rats. Eur. J. Anaesthesiol., 21: 205-209.
PubMed  |  

Han, M.E., K.H. Park, S.Y. Baek, B.S. Kim, J.B. Kim, H.J. Kim and S.O. Oh, 2007. Inhibitory effects of caffeine on hippocampal neurogenesis and function. Biochem. Biophys. Res. Commun., 356: 976-980.
CrossRef  |  PubMed  |  Direct Link  |  

Howell, L.L., V.L. Coffin and R.D. Spealman, 1997. Behavioral and physiological effects of xanthines in nonhuman primates. Psychopharmacology, 129: 1-14.
CrossRef  |  PubMed  |  Direct Link  |  

Johnson, S., J. Iazzetta and C. Dewar, 2003. Severe Raynaud's phenomenon with yohimbine therapy for erectile dysfunction. J. Rheumatol., 30: 2503-2505.
PubMed  |  Direct Link  |  

Kawamata, T., K. Omote, H. Yamamoto, M. Toriyabe, K. Wada and A. Namiki, 2003. Antihyperalgesic and side effects of intrathecal clonidine and tizanidine in a rat model of neuropathic pain. Anesthesiology, 98: 1480-1483.
PubMed  |  Direct Link  |  

Lazarova-Bakarova, M.B., B.P. Petkova, I.K. Todorov and V.D. Petkov, 1991. Memory impairment induced by combined disturbance of noradrenergic and dopaminergic neurotransmissions: Effects of nootropic drugs. Acta Physiol. Pharmacol. Bulgarica, 17: 29-34.
PubMed  |  

MacDonald, E., B.K. Kobilka and M. Scheinin, 1997. Gene targeting-homing in on α₂-adrenoceptor-subtype function. Trends Pharmacol. Sci., 18: 211-219.
PubMed  |  Direct Link  |  

Pan, H.Z. and H.H. Chen, 2007. Hyperalgesia, low-anxiety and impairment of avoidance learning in neonatal caffeine-treated rats. Psychopharmacology, 191: 119-125.
CrossRef  |  PubMed  |  Direct Link  |  

Pare, W., 1961. The effect of caffeine and seconal on a visual discrimination task. J. Comp. Physiol. Psychol., 54: 506-509.
PubMed  |  Direct Link  |  

Paxinos, G. and C. Watson, 1986. The Rat Brain in Stereotaxic Coordinates. 2nd Edn., Academic Press, San Diego, ISBN-10: 0125476213.

Riedel, W., E. Hogervorst, R. Leboux, F. Verhey, H. Van Praag and J. Jolles, 1995. Caffeine attenuates scopolamine-induced memory impairment in humans. Psychopharmacology, 122: 158-168.
PubMed  |  Direct Link  |  

Riedel, W.J. and J. Jolles, 1996. Cognition enhancers in age-related cognitive decline. Drugs Aging, 8: 245-274.
PubMed  |  Direct Link  |  

Sica, D.A., 2007. Centrally acting antihy-pertensive agents: An update. J. Clin. Hypertens. (Greenwich), 9: 399-405.
PubMed  |  Direct Link  |  

Smith, A., C. Brice, J. Nash, N. Rich and D.J. Nutt, 2003. Caffeine and central noradrenaline: Effects on mood, cognitive performance, eye movements and cardiovascular function. J. Psychopharmacol., 17: 283-292.
PubMed  |  Direct Link  |  

Zarrindast, M.R., M. Hadi, H. Homayoun, P. Postami, B. Shafaghi and S. Khavandgar, 2002. The role of alpha-adrenoceptors in the amnestic effect of intracerebroventricular dexamethasone. Pharmacol. Res., 46: 339-344.
CrossRef  |  PubMed  |  Direct Link  |  

Zarrindast, M.R., R. Ahmadi, S. Oryan, K. Parivar and A. Haeri-Rohani, 2002. Effects of alpha-adrenoceptor agonists and antagonists on histamine-induced impairment of memory retention of passive avoidance learning in rats. Eur. J. Pharmacol., 454: 193-198.
CrossRef  |  PubMed  |  Direct Link  |