The responsiveness of individual hypothalamic neurons to microelectrophoretically administered endogenous amines

doi:10.1016/0028-3908(63)90019-4

International Journal of Neuropharmacology

Volume 2, Issues 3–4, August 1963, Pages 181-193

https://doi.org/10.1016/0028-3908(63)90019-4 Get rights and content

Abstract

Responsiveness of individual hypothalamic nerve cells to microelectrophoretically administered acetylcholine (ACh), noradrenaline (NA) and serotonin (5-HT) was investigated. Ninety-eight units responded to one or more of these amines. About equal numbers of ACh-sensitive cells either increased or decreased their spontaneous rate of discharge when tested; NA-sensitive and 5-HT-sensitive units predominantly showed a decreased rate of firing. From histological reconstruction of electrode tracts, it appears that responsive units are diffusely distributed throughout the hypothalamus, although many ACh-sensitive and NA-sensitive cells were encountered in paraventricular and ventral median nuclei. The results are interpreted as compatible with a possible functional role for these endogenous amines in the hypothalamus, although not necessarily as neurohumural transmitters.

Résumé

Nous avons examinéla réceptivitéde cellules nerveuses individuelles de l'hypothalamusàl'acétylcholine (ACh), la noradrénaline (NA) et la sérotonine (5-HT) administrées microélectrophorétiquement. Quatre-vingt dix huit unités réagissaientàune ou plusieurs de ces amines. Des nombresàpeu prèségaux de cellules sensiblesàl'ACh ou bien augmentaient ou diminuaient leur fréquence spontanée de décharge pendant l'épreuve; les unités sensiblesàla NA ou 5-HT montraient surtout une diminution de la fréquence de décharge.

Une reconstruction histologique des traces d'électrodes montre que les unités réceptives sont distribuées d'une facon diffuseàtravers l'hypothalamus bien que beaucoup de cellules sensiblesàl'ACh etàla NA aientétérencontrées dans les noyaux paraventriculaire et ventral médial. Les résultats ontétéinterprétécomme compatibles avec un róle fonctionnel possible de ces amines endogènes dans l'hypothalamus bien que pas necessairement comme transmetteurs neurohumoraux.

Zusammenfassung

Es wurde die Empfindlichkeit individueller hypothalamischer Nervenzellen auf mikroelektrophoretisch zugeführtes Acetylcholin (ACh), Noradrenalin (NA) und Serotonin (5-HT) untersucht. Acht und neunzig Einheiten reagierten auf eines oder mehrere dieser Amine. In einer ungefähr gleichen Anzahl von ACh-empfindlichen Zellen führte der Versuch entweder zu einem Anstieg oder zu einer Abnahme der spontanen Entladungsfrequenz; NA- und 5-HT- empfindliche Einheiten zeigten vorwiegend einen Abfall der Entladungsfrequenz.

Aus histologisch rekonstruierten Elektrodenspuren kann man erschliessen, dass empfindliche Einheiten sich diffusüber den Hypothalamus verteilen, obgleich viele ACh- und NA-empfindliche Zellen im nucleus paraventricularis und im nucleus ventralis medialis angetroffen wurden. Die Ergebnisse werden als vereinbarlich mit einer möglichen Funktion dieser endogenen Amine im Hypothalamus, wenn auch nicht unbedingt in der Rolle von neurohumoralen Ueberträgern, aufgefasst.

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: Preliminary data presented at the 47th Annual Meeting of the Federation of American Societies for Experimental Biology, Atlantic City, N.J. (Bloomet al., 1963).

^*: Author's address-F. E. Bloom, Section on Neurophysiology, Clinical Neuropharmacology Research Center, NIMH, at St. Elizabeth's Hospital, Washington 20, D.C.

View full text

The responsiveness of individual hypothalamic neurons to microelectrophoretically administered endogenous amines

Abstract

Résumé

Zusammenfassung

Electroenceph. clin. Neurophysiol.

Effects of glucose on the activity of hypothalamic “feeding centers”

Science

Response of individual olfactory nerve cells to microelectrophoretically administered chemical substances

Pflügers Arch. ges. Physiol.

Untersuchungen zur Tonisierung einzelner Neurone im hinteren Hypothalamus

Pflügers. Arch. ges. Physiol.

Determination of amines and distribution in brain tissue

J. Neurochem.

Response of individual hypothalamic nerve cells to microelectrophoretically administered substances

The distribution of serotonin, 5-hydroxy-tryptophan decarboxylase, and monoamine oxidase in brain

J. Neurochem.

Excitation and inhibition of brain-stem neurones by nor-adrenaline and acetylcholine

Nature, Lond.

Excitation and inhibition of brain-stem neurones by nor-adrenaline and acetylcholine

Nature, Lond.

Reactions of neurons in or near the supraoptic nuclei

Amer. J. Physiol.

Cholinesterase and succinic dehydrogenase in the central nervous system of the dog

J. Physiol.

Cellular localization of brain monoamines

Acta physiol. scand.

On the localization of acetylcholine receptors

J. Physiol.

Activity of single neurones in the hypothalamus: Effects of osmotic and other stimuli

J. Physiol.

Pharmacological studies upon neurones of the lateral geniculate nucleus of the cat

Brit. J. Pharmacol.

The excitation of Renshaw cells by pharmacological agents applied electrophoretically

J. Physiol.

The effect of diffusional barriers upon the pharmacology of cells within the central nervous system

J. Physiol.

Acidic amino acids with strong excitatory actions on mammalian neurones

J. Physiol.

A new micromanipulator for neurophysiological microelectrode studies

J. Neuropath.