The effect of iontophoretically applied acetylcholine upon the cat's retinal ganglion cells
The effect of iontophoretically applied acetylcholine was tested in 278 retinal ganglion cells of the cat.
26% of 122 ganglion cells were influenced by acetylcholine. In animals, which were pretreated with intravenously administered physostigmine, the proportion of acetylcholine sensitive cells rose to 87%. Acetylcholine had a differential effect upon retinal reaction types. Off-center neurons were excited, On-center neurons were inhibited. The time course of the acetylcholine effect resembled that observed in the cerebral cortex. In a considerable proportion of units, the effect used to diminish with repeated application of the drug (desensitation).
Intravenously applied atropine blocked the excitatory response of Off-center neurons to acetylcholine, but failed to prevent acetylcholine inhibition of On-center neurons. The excitatory response appears thus predominantly mediated by muscarinic receptors. Nicotinic receptors are obviously of little importançe in mediating the response to acetylcholine, since acetylcholine sensitivity remained unchanged after intravenous injection of the curariform agent dihydro-β-erythroidine. Present histochemical and histological knowledge together with our results suggest, that the response of retinal ganglion cells to light stimulation of their receptive field periphery is possibly transmitted through cholinergic amacrine cells.
Key wordsAcetylcholine Physostigmine Microelectrophoresis Ganglion Cells Retina
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- 1.Ames, A., Pollen, D. A.: Neurotransmission in central nervous tissue: A study of isolated rabbit retina. J. Neurophysiol.32, 424–442 (1969).Google Scholar
- 2.Biscoe, T. J., Straugham, D. W.: Micro-electrophoretic studies of neurones in the cat hippocampus. J. Physiol. (Lond.)183, 341–359 (1966).Google Scholar
- 3.Bishop, P. O., Burke, W., Davis, R.: The interpretation of extracellular response of single lateral geniculate cells. J. Physiol. (Lond.)162, 451–462 (1962).Google Scholar
- 4.Bradley, P. B., Dhawan, B. N., Wolstencraft, J. H.: Pharmacological properties of cholinoceptive neurones in the medulla and pons of the cat. J. Physiol. (Lond.)183, 658–674 (1966).Google Scholar
- 5.Crawford, J. M., Curtis, D. R.: Pharmacological studies on feline Betz cells. J. Physiol. (Lond.)186, 121–138 (1966).Google Scholar
- 6.Curtis, D. R., Ryall, R. W.: The acetylcholine receptors of Rhenshaw cells by cholinomimetics. Exp. Brain Res.2, 49–65 (1966).Google Scholar
- 7.Curtis, D. R., Ryall, R. W.: The acetylcholine receptors of Rhenshaw cells. Exp. Brain Res.2, 66–80 (1966).Google Scholar
- 8.Gallego, A.: Campos receptors retineanos. Act. Soc. esp. Cienc. fisiol.2, 177–180 (1955).Google Scholar
- 9.Gallego, A.: Connexions transversales au niveau des couches plexiformes de la retine. Acta Neurophysiol. (Paris) 6e Ser., pp. 5–27 (1965).Google Scholar
- 10.Gruesser, O. J.: A quantitative analysis of spatial summation of excitation and inhibition within receptive field of retinal ganglion cells of cats. Vision Res., Suppl.3, 103–127 (1971).Google Scholar
- 11.Herz, A., Wickelmayer, M., Nacimiento, A.: Über die Herstellung von Mehrfachelektroden für die Mikroelektrophorese. Pflügers Arch. ges. Physiol.284, 95–98 (1965).Google Scholar
- 12.Katz, B., Thesleff, S.: A study of the desensitation produced by acetylcholine at the motor endplate. J. Physiol. (Lond.)138, 63–80 (1951).Google Scholar
- 13.Koelle, G. B., Friedenwald, J. S., Wolfand, L., Allen, R. A.: Localization of specific cholinesterase in ocular tissues of the cat. Amer. J. Opthal.35, 158–1584 (1952).Google Scholar
- 14.Krnjevic, K.: Iontophoretic studies on cortical neurons. Int. Rev. Neurobiol.7, 41–98 (1964).Google Scholar
- 15.Krnjevic, K., Phillis, J. W.: Acetylcholine sensitive cells in the cerebral cortex. J. Physiol. (Lond.)166, 296–327 (1963).Google Scholar
- 16.Nichols, Ch., Koelle, G. B.: Comparison of the localization of acetylcholinesterase and nonspecific cholinesterase activities in mammalian and avian retinas. J. comp. Neurol.133, 1–8 (1968).Google Scholar
- 17.Perwein, J., Straschill, M.: Die Wirkung iontophoretisch applizierten Acetylcholins auf die Aktivität retinaler Ganglienzellen der Katze. Pflügers Arch.332, R93 (1972).Google Scholar
- 18.Straschill, M.: Action of drugs on single neurons in the cat's retina. Vision Res.8, 35–47 (1968).Google Scholar