Some observations on the binding patterns of α-bungarotoxin in the central nervous system of the rat

doi:10.1016/0006-8993(78)90025-2

Brain Research

Volume 157, Issue 2, 24 November 1978, Pages 213-232

https://doi.org/10.1016/0006-8993(78)90025-2 Get rights and content

Summary

Patterns of α-bungarotoxin (αBuTX) binding within the brain of the rat have been studied following one of two procedures: (1) the intraventricular injection of¹²⁵I-labeled toxin followed by a survival period of 1–8 days before aldehyde perfusion, or (2) the incubation of fresh cryostat sections of brain tissue in dilute solutions of radioactive toxin. Appropriate controls with nicotine, curare, atropine and native αBuTX established the specific nature of the binding.

The principal observations were that toxin binding sites are predominantly associated with central areas of the brain in direct receipt of sensory inputs (the main and accessory olfactory bulbs, superior colliculus, ventral lateral geniculate nucleus, cochlear nuclei, the substantia gelatinosa of the spinal cord and spinal trigeminal nucleus, the principal sensory nucleus of the trigeminal, and the dorsal column nuclei) and with limbic areas of the brain (hippocampus, amygdala, olfactory tubercle, medial mammillary nucleus, and the dorsal tegmental nucleus of Gudden). Toxin was not found to bind to cranial motor nuclei with the exception of the dorsal motor nucleus of the vagus and the nucleus ambiguus. The discrete distribution of clusters of silver grains within the granule layer of cerebellar folia I, IX, and X is described as well as the heavy labeling of the inferior and accessory olivary nuclei.

In many areas of the brain silver grains were found to overlie cell bodies. It suggested that this may reflect the presence of both membrane-bound toxin and internalized ligand following initial binding to a membrane receptor site.

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^§: Present address: MRC Neurochemical Pharmacology Unit, Department of Pharmacology, Hills Road, Cambridge CB2 2QD, Great Britain.

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Some observations on the binding patterns of α-bungarotoxin in the central nervous system of the rat

Summary

Biochim. biophys. Acta (Amst.)

Brain Research

Neuropharmacology

Brain Research

Brain Research

Brain Research

Neurosci. Lett.

Brain Research

Exp. Neurol.

Brain Research

Brain Research

Brain Research

Brain Research

Brain Research

Brain Research

Brain Research

Brain Research

Toxicon

Int. Rev. Neurobiol.

Progr. Neurobiol.

Amine receptors in CNS. III. 5-Hydroxytryptamine in brain

Lateral motion of fluorescently labeled acetylcholine receptors in membranes of developing muscle fibers

Cholinergic transmission in subcortical and cortical visual centers of rats: no evidence for the involvement of primary optic system

Exp. Brain Res.

Chemical lesioning of central monoamine axons by means of 5,6-dihydroxytryptamine and 5,7-dihydroxytryptamine

Olfactory relationships of the telencephalon and diencephalon in the rabbit. III. The ipsilateral centrifugal fibers to the olfactory bulbar and retrobulbar formations

J. comp. Neurol.

Acetylcholinesterase neurons in dopamine-containing regions of the brain

J. Neural. Trans.

Fine structure of labeled axons in the cerebellar cortex and nuclei of rodents and primates after intraventricular infusions with tritiated serotonin

Anat. Embryol.

Isolation of neurotoxins from the venom ofBungarus multicinctus and their modes of neuromuscular blocking action

Arch. int. Pharmacodyn. Ther.

Use of a snake venom toxin to characterize the cholinergic receptor protein

Turnover of acetylcholine receptors in skeletal muscle

Possible regulatory function of acetylcholine receptor in maintenance of retinotectal synapses

Nature (Lond.)

Acetylcholine receptors: number and distribution in intact and deafferented superior cervical ganglion of the rat

J. Neurochem.