Acetylcholine release in the hippocampus : regulation by monoaminergic afferents as assessed by in vivo microdialysis
Nilsson, O G LU ; Leanza, G LU and Björklund, A LU
(1992)
In Brain Research
584(1-2).
p.40-132
- Abstract
The role of monoamines in the functional regulation of the septo-hippocampal cholinergic system was studied using in vivo microdialysis of acetylcholine (ACh) release in the hippocampus of awake unrestrained rats. Systemic administration of the dopamine receptor agonist apomorphine (2.0 mg/kg) resulted in a 170% increase in hippocampal ACh overflow. Similarly the catecholamine-releasing agent amphetamine (2.5 mg/kg) produced a 400% increase in ACh overflow. The effect induced by amphetamine, but not that of apomorphine, was blocked in animals pretreated with the tyrosine hydroxylase inhibitor alpha-methyl-p-tyrosine (AMPT). The effect of amphetamine on ACh release was reduced by 75% after a 6-hydroxydopamine (6-OHDA) lesion of the... (More)
The role of monoamines in the functional regulation of the septo-hippocampal cholinergic system was studied using in vivo microdialysis of acetylcholine (ACh) release in the hippocampus of awake unrestrained rats. Systemic administration of the dopamine receptor agonist apomorphine (2.0 mg/kg) resulted in a 170% increase in hippocampal ACh overflow. Similarly the catecholamine-releasing agent amphetamine (2.5 mg/kg) produced a 400% increase in ACh overflow. The effect induced by amphetamine, but not that of apomorphine, was blocked in animals pretreated with the tyrosine hydroxylase inhibitor alpha-methyl-p-tyrosine (AMPT). The effect of amphetamine on ACh release was reduced by 75% after a 6-hydroxydopamine (6-OHDA) lesion of the ventral tegmental area (VTA) but was not affected by 6-OHDA lesions of the noradrenergic dorsal and ventral bundles. However, baseline ACh overflow was increased by 130% by the dorsal and ventral bundle lesions. The serotonin-releasing agent p-chloroamphetamine (2.5 mg/kg) produced a 160% increase in hippocampal ACh release, and this effect was enhanced after a 5,7-dihydroxytryptamine (5,7-DHT) lesion of the serotonin projection system. The results show that surgical or pharmacological manipulations of the ascending brainstem monoaminergic systems, which innervate wide areas of the forebrain, including the septum and the hippocampal formation, have pronounced effects on septo-hippocampal cholinergic activity. Thus, the present data provide support for the view that information regarding behavioral state and arousal is conveyed to the septo-hippocampal system via ascending monoaminergic systems.
(Less)
- author
- Nilsson, O G
LU
; Leanza, G
LU
and Björklund, A
LU
- organization
- publishing date
- 1992-07-03
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- 5,7-Dihydroxytryptamine/toxicity, Acetylcholine/metabolism, Amphetamine/pharmacology, Animals, Apomorphine/pharmacology, Dialysis, Dopamine/physiology, Female, Hippocampus/metabolism, In Vitro Techniques, Methyltyrosines/pharmacology, Neurons, Afferent/metabolism, Norepinephrine/physiology, Prosencephalon/physiology, Rats, Rats, Inbred Strains, Serotonin/physiology, Synaptic Transmission/drug effects, Tyrosine 3-Monooxygenase/antagonists & inhibitors, alpha-Methyltyrosine, p-Chloroamphetamine/toxicity
- in
- Brain Research
- volume
- 584
- issue
- 1-2
- pages
- 9 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:0026693231
- pmid:1355389
- ISSN
- 0006-8993
- DOI
- 10.1016/0006-8993(92)90886-e
- language
- English
- LU publication?
- yes
- id
- 22a38ba9-c4c6-48d0-a9d0-5889fcb73bf2
- date added to LUP
- 2019-06-25 10:04:57
- date last changed
- 2024-02-15 15:55:41
@article{22a38ba9-c4c6-48d0-a9d0-5889fcb73bf2,
abstract = {{<p>The role of monoamines in the functional regulation of the septo-hippocampal cholinergic system was studied using in vivo microdialysis of acetylcholine (ACh) release in the hippocampus of awake unrestrained rats. Systemic administration of the dopamine receptor agonist apomorphine (2.0 mg/kg) resulted in a 170% increase in hippocampal ACh overflow. Similarly the catecholamine-releasing agent amphetamine (2.5 mg/kg) produced a 400% increase in ACh overflow. The effect induced by amphetamine, but not that of apomorphine, was blocked in animals pretreated with the tyrosine hydroxylase inhibitor alpha-methyl-p-tyrosine (AMPT). The effect of amphetamine on ACh release was reduced by 75% after a 6-hydroxydopamine (6-OHDA) lesion of the ventral tegmental area (VTA) but was not affected by 6-OHDA lesions of the noradrenergic dorsal and ventral bundles. However, baseline ACh overflow was increased by 130% by the dorsal and ventral bundle lesions. The serotonin-releasing agent p-chloroamphetamine (2.5 mg/kg) produced a 160% increase in hippocampal ACh release, and this effect was enhanced after a 5,7-dihydroxytryptamine (5,7-DHT) lesion of the serotonin projection system. The results show that surgical or pharmacological manipulations of the ascending brainstem monoaminergic systems, which innervate wide areas of the forebrain, including the septum and the hippocampal formation, have pronounced effects on septo-hippocampal cholinergic activity. Thus, the present data provide support for the view that information regarding behavioral state and arousal is conveyed to the septo-hippocampal system via ascending monoaminergic systems.</p>}},
author = {{Nilsson, O G and Leanza, G and Björklund, A}},
issn = {{0006-8993}},
keywords = {{5,7-Dihydroxytryptamine/toxicity; Acetylcholine/metabolism; Amphetamine/pharmacology; Animals; Apomorphine/pharmacology; Dialysis; Dopamine/physiology; Female; Hippocampus/metabolism; In Vitro Techniques; Methyltyrosines/pharmacology; Neurons, Afferent/metabolism; Norepinephrine/physiology; Prosencephalon/physiology; Rats; Rats, Inbred Strains; Serotonin/physiology; Synaptic Transmission/drug effects; Tyrosine 3-Monooxygenase/antagonists & inhibitors; alpha-Methyltyrosine; p-Chloroamphetamine/toxicity}},
language = {{eng}},
month = {{07}},
number = {{1-2}},
pages = {{40--132}},
publisher = {{Elsevier}},
series = {{Brain Research}},
title = {{Acetylcholine release in the hippocampus : regulation by monoaminergic afferents as assessed by in vivo microdialysis}},
url = {{http://dx.doi.org/10.1016/0006-8993(92)90886-e}},
doi = {{10.1016/0006-8993(92)90886-e}},
volume = {{584}},
year = {{1992}},
}