Abstract
In order to obtain further evidence of the pharmacological effects of retention-facilitating substances, the influence of sodium-orotate, methylglucamine orotate, and pirazetam on the bioelectrical activity of central nervous system structures were studied. Sodium orotate showed no influence on the cortical and hippocampal spontaneous EEGs of conscious nonimmobilized rabbits. The amplitude of the first surface-positive wave of the cortical evoked potential that was elicited by stimulation of tooth pulp was, however, significantly increased in long-lasting terms by both pirazetam and the two salts of orotic acid. Similarly, the three substances also influenced the changes in excitability induced by PTP of tooth pulp. The findings suggest that these chemicals facilitate in nonspecific manner responses to externally applied stimuli through central structures. The relationships between the altered stimulus response and the retention-facilitating action of these substances are discussed.
Similar content being viewed by others
References
Borbely A. A.: Pharmacological modifications of evoked brain potentials Berne-Stuttgart-Vienna Huber (1973)
Eccles, J. C.: Possible ways in which synaptic mechanisms participate in learning, remembering and forgetting. In. The anatomy of memory, Vol. 1, D. P. Kimble, ed., pp. 12–87, Palo Alto: Science and Behavior Books 1965
Esplin, D. W.: Effects of diphenylhydantoin on synaptic transmission in cat spinal cord and stellate ganglion. J. Pharmacol. exp. Ther. 120, 301–323 (1957)
Giurgea, C. E.: New approaches to the pharmacology of the brain. In: N.A.T.O. Symposium “Drugs, Sleep, and Behaviour”. Aviemore 1972
Giurgea, C. E., Moyersoons, F. E.: On the pharmacology of cortical evoked potentials. Arch. int. Pharmacodyn. 199, 67–78 (1972)
Hahn, F.: Analeptics. Pharmacol. Rev. 12, 447–530 (1960)
Izquierdo, I.: Hippocampal physiology. Experiments on regulation of its electrical activity on the mechanism of seizures and on an hypothesis of learning. Behav. Biol. 7, 669–698 (1972)
Kandel, E. R., Spencer, W. A.: Cellular neurophysiological approaches in the study of learning. Physiol. Rev. 48, 65–135 (1968)
Khazan, N.: Electrophysiological correlates of the action of drugs in the brain. In: An introduction to psychopharmacology, R. H. Rech and K. E. Moore, eds., pp. 175–211 New York: Raven Press 1971
Killam, E. K.: Drug action on the brainstem reticular formation. Pharmacol. Rev. 14, 175–223 (1962)
Krug, M., Schmidt, J.: Langdauernde Erregbarkeitsänderungen im sensomotorischen Kortex von Kaninchen nach tetanischer Reizung der Zahnpulpa. Acta biol. med. germ. 34, 135–141 (1975)
Krug, M., Schmidt, J., Kluba, U., Kluba, J.: Der Einfluß von RNS-Präkursoren auf neokortikale Fazilitationsprozesse. 16th Annual Meeting of the GDR Society of Pharmacology and Toxicology, Zinnowitz, September 25–28, 1974
Longo, V., Loizzo, A.: Effects of drugs on the hippocampal θ-rhythm. Possible relationships to learning and memory processes. In. Pharmacology and the Future of Man. Proc. 5th Int. Congress on Pharmacology, San Francisco 1972, Vol. 4, pp 46–54 Basel: Karger 1973
Matthies, H.: The intracellular regulation of the interneuronal connectivity-the molecular foundation of learning processes. Ergebn. exp. Med. 10, 25–55 (1972)
Matthies, H., Lietz, W.: Die Bedeutung der Applikationsart und Applikationsdauer für die Wirkung von Orotsäure auf ein einfaches Modell eines Lernvorganges. Acta biol. med. germ. 19, 1053–1055 (1967)
McGaugh, J. L.: Modification of learning and memory by CNS-stimulants and electrical stimulation of the brain. In: Pharmacology and the future of man. Proc. 5th Int. Congress on Pharmacology, San Francisco 1972, Vol. 4, pp. 39–45, Basel:Karger 1973
McGaugh, J. L., Petrinovich, L. F.: Effects of drugs on learning and memory. Int. Rev. Neurobiol. 8, 139–196 (1965)
Monnier, M., Gangloff, H.: Atlas for stereotaxic brain research on conscious rabbit. Amsterdam-London-New York: Elsevier 1962
Myslivecek, J., Hassmanova, J.: An electrophysiological analysis of action of Pirazetam in rats. Activ. nerv. sup. (Praha) 16, 242–244 (1974)
Ott, T., Lössner, B., Matthies, H.: Die Wirkung von Nucleotid-Monophosphaten auf die Acquisition und Extinktion bedingter Reaktionen. Psychopharmacologia (Berl.) 23, 261–271 (1972)
Ott, T., Matthies, H.: Die Wirkung von Orotsäure auf die durch elektrokonvulsiven Schock ausgelöste retrograde Amnesie. Psychopharmacologia (Berl.) 20, 16–21 (1971)
Ott, T., Matthies, H.: Significance of RNA precursors in the formation and maintenance of long-term memory: Pre- and posttraining hippocampal and cortical applications of RNA precursors. Psychopharmacologia (Berl.) 28, 195–204 (1973)
Roberts, C. A.: Anticonvulsant effects of uridine: Comparative analysis of metrazol and penicillin induced foci. Brain Res. 55, 291–308 (1973)
Rüthrich, H.-L., Pohle, W., Matthies H.: Increase of guanosine incorporation into RNA of hippocampal neurones by application of uridine monophosphate during a learning experiment. Brain Res. 69, 49–55 (1974)
Schmidt, J. Guhlke, I.: Die Beeinflussung kortikaler Fazilitations-und Depressionsvorgänge durch Strychnin, Pikrotoxin und Pentetrazol. Acta biol. med. germ. 23, 659–668 (1969)
Schmidt, J., Kluba, J., Kluba, U. Der Einfluß von Orotsäure auf durch exterozeptive Reize ausgelöste kortikale Potentiale. Acta biol. med. germ. 33, 211–222 (1974)
Schulzeck, S., Popov, N., Kammerer, E., Matthies, H.: Die Verteilung der Orotsäure in einigen Organen der Ratte. Ergebn. exp. Med. 3, 295–298 (1970)
Suria, A., Costa, E.: Benzodiazepines and posttetanic potentiation in sympathetic ganglia of the bullfrog. Brain Res. 50, 235–239 (1973)
Valdman, A. V.: Pharmacology of the brain. Progr. Brain Res. 20, 1–92 (1967)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Krug, M., Ott, T., Schulzeck, K. et al. Effects of orotic acid and pirazetam on cortical bioelectrical activity in rabbits. Psychopharmacology 53, 73–78 (1977). https://doi.org/10.1007/BF00426696
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00426696