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Morphological analysis of aminergic modulation of noradrenaline neurons in the locus coeruleus of rat: Serotonin input vs adrenaline input
5708
34. Neurotransmitters
II. Monoamines
Catecholaminergic terminals in the medial prefrontal and anterior cingulate cortices of the rat: Immunohistochemistry and electronm$roscopy. KIKUKO IMAWYIX AND BRIGITTE BERGER Department of Anatomy, Shiga University of Medical Science, Otsu, Shida 520-21 Japan andTNSERM U-106, Paris, France
Sprague-Dawley rats streotaxically received an unilateral injection of B-CHDA (8ug/2ul) into the MFB under anesthesia with 35% chloral hydrate. After 1-7 clays,anesthetized rats were perfused end brain sections were processed for TH and DBH immmohistochemistries by streptavidin-biotin method. Using a computer-based Me analyzer , quantitative data was obtained. The nlrmbersof T&positive varicosities were 100/5600 $in layer V/VI of the prefrontal cortex and 90/56OO,&in layer IK of the anterior cingulate cortex, while DBH-positive ones were 40/56OO&in layer I end 20 in other layers. Electronmicroscopy clarified that TH immunoreaotion products lay on small and large synaptic vesicles and microtubules, but not on mitoohondria. TH-positive houtons rarely made a synaptic junction (4%). However, they often came in contact with non-TH axospinous synapses forming "triad" relationships. It may suggest that TH boutons subserve control of cortical input. Neurotoxic 6-OHDA induced a numerical reduction of 'I% and DBH-positive varicosities (TH: to 20%, DBH: to 40% of the control). Thus, terminal degeneration was confirmed in all regions, especially as prominent dense granular bodies in layer IU of ACv and ACd. Most of the degenerating boutons wre surrounded by astroglial endfeet, but more than 15% of them clearly displayed a synaptic junction with a dendritic spine. This is rather inconsistent with the low incidence of synaptic junctions on TH boutons. To explain this fact, several possibilities are considered.
MORPHOLOGICAL ANALYSIS OF AMINERGIC MODULATION OF NORADRENALINE NEURONS LOCUS COERULEUS OF RAT: SEROTONIN INPUT VS ADRENALINE INPUT. AND HIROSHI KIMURA3, 'Department of KUNIO KITAHAMW TOSHIHIRO MAEDA',
IN
THE
Anatomy
Japan and =Departement de University Universite Claude Bernard, Lyon 69008, France. Medecine Experimentale, of serotonin(5HT) and phenylethanolamine-NThe input-target size histogram revealed two populations varicosities inununoreactive methyltransferase(PNMT) 5HT-immunoreactive terminals were from each other. clearly distinguishable while PNMT smaller in size and were in contact with smaller-sized dendrites, The incidence of terminal terminals and their targets were of larger size. 5HTprofiles showing synaptic specialization also differed in the two groups. and PNMT-immunoreactive boutons showed 30% and 18% of incidence, respectively. Two similar populations were indicated in total aminergic inputs by monoamine Amine-amine amine-nonamine and histogram. size input-target oxidase(MA0) contacts showed a quite similar relationship to that seen between the PNMT and as to size of terminal-dendrite and incidence of specialization. 5HT terminals, the adrenaline neurons terminate upon noradrenaline neurons Taken together, on the other of the locus coeruleus and may directly affect their activities: them via non-aminergic interneurons. hand, 5HT input may influence
SUBSTANCE P-ERGIC INPUTS IN RAT VEINTRAL TEGMENTAL DOPAMINERGIC NEURONS QC5IVE AND HIROSHI TOSHIKAZU ASA SHINOBU INAGAKI.4A"4A"d11RlfOJI TAMIYAL--_I--L---_ _-First Department of Anatomy, Osaks City University Medical School, l4-54 Asahi-machi, Abenoku, Osaka, 545, and 'Department of Neuropsychiatry, Kinki University School of Medicine, Ohno-higashi, Osaka-sayama, 589 Japan. Pharmacological and physiological studies have suggested a close relationship between dopamine (DA) and substance P (SP) in the ventral tegmental area (VTA). However, no direct evidence has been reported so far at the synaptic level where OCCUX-S, chemical neurotransmission actually We attempted to identify whether dopaminergic neurons are in direct synaptic contact with SP afferents in the VTA. By the immunoelectron microscopic mirror method, two confronting surfaces from a pair of consecutive sections, one of which had been immunostained for tyrosine hydroxylase (TH, the enzyme that synthesizes catecholamines) and the other for SP, were observed under light and electron microscopes. Of 14 neurons examined in serial sections from SP-immunostained sections, 4 neurons identified as dopaminergic neurons could be seen to receive synaptic inputs from SPand proximal dendritic shafts. The immunoreactive somata terminals on their This suggests that contacts showed both asymmetrical and symmetrical synapses. via SP afferents have a direct influence on dopaminergic neurons in the VTA these synaptic contacts.
34. Neurotransmitters
II. Monoamines
Catecholaminergic terminals in the medial prefrontal and anterior cingulate cortices of the rat: Immunohistochemistry and electronm$roscopy. KIKUKO IMAWYIX AND BRIGITTE BERGER Department of Anatomy, Shiga University of Medical Science, Otsu, Shida 520-21 Japan andTNSERM U-106, Paris, France
Sprague-Dawley rats streotaxically received an unilateral injection of B-CHDA (8ug/2ul) into the MFB under anesthesia with 35% chloral hydrate. After 1-7 clays,anesthetized rats were perfused end brain sections were processed for TH and DBH immmohistochemistries by streptavidin-biotin method. Using a computer-based Me analyzer , quantitative data was obtained. The nlrmbersof T&positive varicosities were 100/5600 $in layer V/VI of the prefrontal cortex and 90/56OO,&in layer IK of the anterior cingulate cortex, while DBH-positive ones were 40/56OO&in layer I end 20 in other layers. Electronmicroscopy clarified that TH immunoreaotion products lay on small and large synaptic vesicles and microtubules, but not on mitoohondria. TH-positive houtons rarely made a synaptic junction (4%). However, they often came in contact with non-TH axospinous synapses forming "triad" relationships. It may suggest that TH boutons subserve control of cortical input. Neurotoxic 6-OHDA induced a numerical reduction of 'I% and DBH-positive varicosities (TH: to 20%, DBH: to 40% of the control). Thus, terminal degeneration was confirmed in all regions, especially as prominent dense granular bodies in layer IU of ACv and ACd. Most of the degenerating boutons wre surrounded by astroglial endfeet, but more than 15% of them clearly displayed a synaptic junction with a dendritic spine. This is rather inconsistent with the low incidence of synaptic junctions on TH boutons. To explain this fact, several possibilities are considered.
MORPHOLOGICAL ANALYSIS OF AMINERGIC MODULATION OF NORADRENALINE NEURONS LOCUS COERULEUS OF RAT: SEROTONIN INPUT VS ADRENALINE INPUT. AND HIROSHI KIMURA3, 'Department of KUNIO KITAHAMW TOSHIHIRO MAEDA',
IN
THE
Anatomy
Japan and =Departement de University Universite Claude Bernard, Lyon 69008, France. Medecine Experimentale, of serotonin(5HT) and phenylethanolamine-NThe input-target size histogram revealed two populations varicosities inununoreactive methyltransferase(PNMT) 5HT-immunoreactive terminals were from each other. clearly distinguishable while PNMT smaller in size and were in contact with smaller-sized dendrites, The incidence of terminal terminals and their targets were of larger size. 5HTprofiles showing synaptic specialization also differed in the two groups. and PNMT-immunoreactive boutons showed 30% and 18% of incidence, respectively. Two similar populations were indicated in total aminergic inputs by monoamine Amine-amine amine-nonamine and histogram. size input-target oxidase(MA0) contacts showed a quite similar relationship to that seen between the PNMT and as to size of terminal-dendrite and incidence of specialization. 5HT terminals, the adrenaline neurons terminate upon noradrenaline neurons Taken together, on the other of the locus coeruleus and may directly affect their activities: them via non-aminergic interneurons. hand, 5HT input may influence
SUBSTANCE P-ERGIC INPUTS IN RAT VEINTRAL TEGMENTAL DOPAMINERGIC NEURONS QC5IVE AND HIROSHI TOSHIKAZU ASA SHINOBU INAGAKI.4A"4A"d11RlfOJI TAMIYAL--_I--L---_ _-First Department of Anatomy, Osaks City University Medical School, l4-54 Asahi-machi, Abenoku, Osaka, 545, and 'Department of Neuropsychiatry, Kinki University School of Medicine, Ohno-higashi, Osaka-sayama, 589 Japan. Pharmacological and physiological studies have suggested a close relationship between dopamine (DA) and substance P (SP) in the ventral tegmental area (VTA). However, no direct evidence has been reported so far at the synaptic level where OCCUX-S, chemical neurotransmission actually We attempted to identify whether dopaminergic neurons are in direct synaptic contact with SP afferents in the VTA. By the immunoelectron microscopic mirror method, two confronting surfaces from a pair of consecutive sections, one of which had been immunostained for tyrosine hydroxylase (TH, the enzyme that synthesizes catecholamines) and the other for SP, were observed under light and electron microscopes. Of 14 neurons examined in serial sections from SP-immunostained sections, 4 neurons identified as dopaminergic neurons could be seen to receive synaptic inputs from SPand proximal dendritic shafts. The immunoreactive somata terminals on their This suggests that contacts showed both asymmetrical and symmetrical synapses. via SP afferents have a direct influence on dopaminergic neurons in the VTA these synaptic contacts.