1
|
Kononenko NL, Hartfil S, Willer J, Ferch J, Wolfenberg H, Pflüger HJ. A population of descending tyraminergic/octopaminergic projection neurons of the insect deutocerebrum. J Comp Neurol 2018; 527:1027-1038. [PMID: 30444529 DOI: 10.1002/cne.24583] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 09/27/2018] [Accepted: 10/23/2018] [Indexed: 02/02/2023]
Abstract
In this study, we describe a cluster of tyraminergic/octopaminergic neurons in the lateral dorsal deutocerebrum of desert locusts (Schistocerca gregaria) with descending axons to the abdominal ganglia. In the locust, these neurons synthesize octopamine from tyramine stress-dependently. Electrophysiological recordings in locusts reveal that they respond to mechanosensory touch stimuli delivered to various parts of the body including the antennae. A similar cluster of tyraminergic/octopaminergic neurons was also identified in the American cockroach (Periplaneta americana) and the pink winged stick insect (Sipyloidea sipylus). It is suggested that these neurons release octopamine in the ventral nerve cord ganglia and, most likely, convey information on arousal and/or stressful stimuli to neuronal circuits thus contributing to the many actions of octopamine in the central nervous system.
Collapse
Affiliation(s)
| | - Sergej Hartfil
- Freie Universität Berlin, Institut für Biologie, Berlin, Germany
| | - Julia Willer
- Freie Universität Berlin, Institut für Biologie, Berlin, Germany
| | - Jessica Ferch
- Freie Universität Berlin, Institut für Biologie, Berlin, Germany
| | - Heike Wolfenberg
- Freie Universität Berlin, Institut für Biologie, Berlin, Germany
| | | |
Collapse
|
2
|
Matsuyama S, Nagao T, Sasaki K. Consumption of tyrosine in royal jelly increases brain levels of dopamine and tyramine and promotes transition from normal to reproductive workers in queenless honey bee colonies. Gen Comp Endocrinol 2015; 211:1-8. [PMID: 25448251 DOI: 10.1016/j.ygcen.2014.11.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 10/22/2014] [Accepted: 11/04/2014] [Indexed: 11/30/2022]
Abstract
Dopamine (DA) and tyramine (TA) have neurohormonal roles in the production of reproductive workers in queenless colonies of honey bees, but the regulation of these biogenic amines in the brain are still largely unclear. Nutrition is an important factor in promoting reproduction and might be involved in the regulation of these biogenic amines in the brain. To test this hypothesis, we examined the effect of oral treatments of tyrosine (Tyr; a common precursor of DA, TA and octopamine, and a component of royal jelly) in queenless workers and quantified the resulting production of biogenic amines. Tyrosine treatments enhanced the levels of DA, TA and their metabolites in the brain. Workers fed royal jelly had significantly larger brain levels of Tyr, DA, TA and the metabolites in the brains compared with those bees fed honey or sucrose (control). Treatment with Tyr also inhibited the behavior of workers outside of the hive and promoted ovarian development. These results suggest that there is a link between nutrition and the regulation of DA and TA in the brain to promote the production of reproductive workers in queenless honey bee colonies.
Collapse
Affiliation(s)
- Syuhei Matsuyama
- Graduate Program in Bioscience and Chemistry, Human Information Systems, Kanazawa Institute of Technology, 3-1 Yakkaho, Hakusan, Ishikawa 924-0838, Japan
| | - Takashi Nagao
- Graduate Program in Bioscience and Chemistry, Human Information Systems, Kanazawa Institute of Technology, 3-1 Yakkaho, Hakusan, Ishikawa 924-0838, Japan
| | - Ken Sasaki
- Graduate Program in Bioscience and Chemistry, Human Information Systems, Kanazawa Institute of Technology, 3-1 Yakkaho, Hakusan, Ishikawa 924-0838, Japan; Department of Bioresource Science, Tamagawa University, Machida, Tokyo 194-8610, Japan.
| |
Collapse
|
3
|
Wong R, Lange AB. Octopamine modulates a central pattern generator associated with egg-laying in the locust, Locusta migratoria. JOURNAL OF INSECT PHYSIOLOGY 2014; 63:1-8. [PMID: 24530620 DOI: 10.1016/j.jinsphys.2014.02.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 01/30/2014] [Accepted: 02/05/2014] [Indexed: 06/03/2023]
Abstract
Egg-laying in Locusta migratoria involves the control of a variety of complex behavioural patterns including those that regulate digging of the oviposition hole and retention of eggs during digging. These two behavioural patterns are under the control of central pattern generators (CPGs). The digging and egg-retention CPGs are coordinated and integrated with overlapping locations of neural substrate within the VIIth and VIIIth abdominal ganglia of the central nervous system (CNS). In fact, the egg-retention CPG of the VIIth abdominal ganglion is involved in both egg-retention and protraction of the abdomen during digging. The biogenic amine, octopamine, has peripheral effects on oviduct muscle, relaxing basal tension of the lateral and upper common oviduct and enabling egg passage. Here we show that octopamine also modulates the pattern of the egg-retention CPG by altering the motor pattern that controls the external ventral protractor of the VIIth abdominal segment. There is no change in the motor pattern that goes to the oviducts. Octopamine decreased the frequency of the largest amplitude action potential and decreased burst duration while leading to an increase in cycle duration and interburst interval. The effects of octopamine were greatly reduced in the presence of the α-adrenergic blocker, phentolamine, indicating that the action of octopamine was via a receptor. Thus, octopamine orchestrates events that can lead to oviposition, centrally inhibiting the digging behavior and peripherally relaxing the lateral and common oviducts to enable egg-laying.
Collapse
Affiliation(s)
- Raymond Wong
- University of Toronto Mississauga, Department of Biology, 3359 Mississauga Rd., Mississauga, ON L5L 1C6, Canada
| | - Angela B Lange
- University of Toronto Mississauga, Department of Biology, 3359 Mississauga Rd., Mississauga, ON L5L 1C6, Canada.
| |
Collapse
|
4
|
Newland PL, Yates P. Nitrergic modulation of an oviposition digging rhythm in locusts. ACTA ACUST UNITED AC 2008; 210:4448-56. [PMID: 18055633 DOI: 10.1242/jeb.010009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In locusts, a central pattern generator underlies the rhythmic movements of the ovipositor valves that serve to drive the abdomen into damp soil in order to lay eggs. We have investigated the role of nitric oxide (NO) in the control of this oviposition digging rhythm. NO increases the frequency of the rhythm by acting via sGC to elevate cGMP, which in turn acts via PKG. Increasing exogenous NO levels using the NO donors SNAP and PAPANONOate increased the cycle frequency of the fictive digging rhythm, as did increasing endogenous NO by bath application of the substrate for NOS, l-arginine. On the other hand, application of the NO scavenger PTIO decreased the cycle frequency, indicating that NO must normally exert a continuous and dynamic role on the central pattern generator underlying the oviposition rhythm. Inhibiting the main molecular target of NO, soluble guanylate cyclase, with ODQ reduced the cycle frequency of the rhythm, suggesting that NO mediated its effects via sGC and cyclic GMP. Further evidence for this was produced by bath application of 8-Br-cGMP, which increased the frequency of the rhythm. Bath application of the generic protein kinase inhibitor and a selective PKG inhibitor, H-7 and KT-5823, respectively, reduced the frequency of the rhythm, suggesting that PKG acted as a target for cGMP. Thus, we conclude that NO plays a key role in regulating the frequency of the central pattern generator controlling rhythmic egg-laying movements in locusts by acting via sGC/cGMP-PKG.
Collapse
Affiliation(s)
- Philip L Newland
- School of Biological Sciences, Biomedical Science Building, University of Southampton, Bassett Crescent East, Southampton, UK.
| | | |
Collapse
|
5
|
Hirashima A, Yamaji H, Yoshizawa T, Kuwano E, Eto M. Effect of tyramine and stress on sex-pheromone production in the pre- and post-mating silkworm moth, Bombyx mori. JOURNAL OF INSECT PHYSIOLOGY 2007; 53:1242-9. [PMID: 17681526 DOI: 10.1016/j.jinsphys.2007.06.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Revised: 06/22/2007] [Accepted: 06/25/2007] [Indexed: 05/16/2023]
Abstract
Tyramine (TA) increased significantly after mating, whereas there were no significant differences in octopamine (OA) and dopamine (DA) levels in the brain-suboesophageal ganglion (SOG) complexes between virgin and mated females. The effects of various biogenic amines were tested on pheromone production of virgin and mated females of the silkworm moth, Bombyx mori. After 8h a significant reduction by TA (46%) was observed. Meanwhile, when OA or DA was injected, a significant increase of pheromone titer was observed in both virgin and mated females. This study also presents evidence for an increase in levels of OA and DA in the brain-SOG complexes in response to mechanical stress in B. mori female. TA suppressed pheromone production in an in vitro pheromone gland (PG) homogenate preparation, thus suggesting that the target of TA is the PG. TA inhibited pheromone production in vitro in a dose-dependent manner and DA had a lower inhibitory activity than TA, whereas OA had no effect, suggesting that TA is a candidate for regulating pheromone production in the PG, although other factors could be responsible for the pheromonostatic function.
Collapse
Affiliation(s)
- Akinori Hirashima
- Department of Applied Genetics and Pest Management, Faculty of Agriculture, Graduate School, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
| | | | | | | | | |
Collapse
|
6
|
Rodríguez-Valentín R, López-González I, Jorquera R, Labarca P, Zurita M, Reynaud E. Oviduct contraction in Drosophila is modulated by a neural network that is both, octopaminergic and glutamatergic. J Cell Physiol 2006; 209:183-98. [PMID: 16826564 DOI: 10.1002/jcp.20722] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Fertility is a highly complex and regulated phenomenon essential for the survival of any species. To identify Drosophila fertility-specific neural networks, we used a GAL4/UAS enhancer trap genetic screen that selectively inactivates groups of neurons. We identified a GAL4 line (bwktqs) that has a female sterile phenotype only when it expresses the tetanus toxin light chain (TeTxLC). These flies lack oviduct contraction, lay almost no eggs, sperm accumulate in the oviducts, and fewer than normal are seen in the storage organs. In insects, two neuroactive substances are important for oviduct contraction: octopamine (OA), a monoamine that inhibits oviduct contraction, and glutamate (Glu), a neurotransmitter that induces contraction. It is known that octopaminergic neurons of the thoracic abdominal ganglion (TAG) modulate oviduct contraction, however, the glutamatergic neurons that innervate the oviduct have not been identified yet and the interaction between these two neuroactive substances is not well understood. Immunostaining experiments revealed that the bwktqs line trapped an octopaminergic neural network that innervates the genital tract. We show that wt like oviduct contraction in TeTxLC-inactivated flies can only be rescued by simultaneous application of Glu and OA suggesting that the abdominal bwktqs neurons are both octopaminergic and glutamatergic, the use of an agonist and an antagonist for Glu receptors as well as their direct visualization confirmed its participation in this phenomenon. Our work provides the first evidence that adult abdominal type II visceral innervations co-express Glu and OA and allows us to re-evaluate the previous model of neuronal network controlling insect oviduct contraction.
Collapse
Affiliation(s)
- Rocío Rodríguez-Valentín
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, México
| | | | | | | | | | | |
Collapse
|
7
|
Monastirioti M. Distinct octopamine cell population residing in the CNS abdominal ganglion controls ovulation in Drosophila melanogaster. Dev Biol 2004; 264:38-49. [PMID: 14623230 DOI: 10.1016/j.ydbio.2003.07.019] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Octopamine is an important neuroactive substance that modulates several physiological functions and behaviors of invertebrate species. Its biosynthesis involves two steps, one of which is catalyzed by Tyramine beta-hydroxylase enzyme (TBH). The Tbetah gene has been previously cloned from Drosophila melanogaster, and null mutations have been generated resulting in octopamine-less flies that show profound female sterility. Here, I show that ovulation process is defective in the mutant females resulting in blockage of mature oocytes within the ovaries. The phenotype is conditionally rescued by expressing a Tbetah cDNA under the control of a hsp70 promoter in adult females. Fertility of the mutant females is also restored when TBH is expressed, via the GAL4-UAS system, in cells of the CNS abdominal ganglion that express TBH and produce octopamine. This neuronal population differs from the dopamine- and serotonin-expressing cells indicating distinct patterns of expression and function of the three substances in the region. Finally, I demonstrate that these TBH-expressing cells project to the periphery where they innervate the ovaries and the oviducts of the reproductive system. The above results point to a neuronal focus that can synthesize and release octopamine in specific sites of the female reproductive system where the amine is required to trigger ovulation.
Collapse
Affiliation(s)
- Maria Monastirioti
- Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology-Hellas, 71110 Heraklion, Crete, Greece.
| |
Collapse
|
8
|
Gruntenko NE, Wilson TG, Monastirioti M, Rauschenbach IY. Stress-reactivity and juvenile hormone degradation in Drosophila melanogaster strains having stress-related mutations. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2000; 30:775-783. [PMID: 10876121 DOI: 10.1016/s0965-1748(00)00049-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Juvenile hormone (JH) degradation was studied under normal and stress conditions in young and matured females of Drosophila melanogaster strains having mutations in different genes involved in responses to stress It was shown that (1) the impairment in heat shock response elicits an alteration in stress-reactivity of the JH system; (2) the impairment JH reception causes a decrease of JH-hydrolysing activity and of stress-reactivity in young females, while in mature ones stress reactivity is completely absent; (3) the absence of octopamine results in higher JH-hydrolysis level under normal conditions and altered JH stress-reactivity; (4) the higher dopamine content elicits a dramatic decrease of JH degradation under normal conditions and of JH stress-reactivity. Thus, the impairments in any component of the Drosophila stress reaction result in changes in the reponse of JH degradation system to stress. The role of JH in the development of the insect stress reaction is discussed.
Collapse
Affiliation(s)
- N E Gruntenko
- Institute of Cytology and Genetics, Russian Academy of Sciences, Siberian Division, 630090, Novosibirsk, Russia.
| | | | | | | |
Collapse
|
9
|
Morris OT, Duch C, Stevenson PA. Differential activation of octopaminergic (DUM) neurones via proprioceptors responding to flight muscle contractions in the locust. J Exp Biol 1999; 202 Pt 24:3555-64. [PMID: 10574732 DOI: 10.1242/jeb.202.24.3555] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The synaptic potentials generated in neuromodulatory octopaminergic dorsal unpaired median (DUM) neurones by afferents excited by twitch contractions of a dorso-ventral flight muscle were investigated in the locust. Responses to stimulation of the metathoracic wing elevator muscle 113 were obtained in locusts in which all sensory feedback from the thorax had been removed, except for feedback from the thoracic chordotonal organs, the axons of which enter via the purely sensory nerve 2. Afferents in nerve 2C, which originates from two chordotonal organs, responded reliably to twitch contractions of this flight muscle. Octopaminergic neurones innervating leg muscles (DUM5 neurones) received depolarising inputs and often spiked following stimulation of the muscle. In contrast, those innervating the wing muscles themselves (DUM3 and DUM3,4 neurones) received inhibitory inputs. The responses of DUM3,4,5 neurones, which project mainly to leg muscles, were more complex: most were excited by twitch contractions of M113 but some were inhibited. DUMDL, which innervates the dorsal longitudinal indirect flight muscles, showed no clear response. Direct stimulation of nerve 2C evoked depolarising inputs and spikes in DUM5 neurones and hyperpolarising inputs in DUM3 and DUM3,4 neurones. Our data suggest that sensory feedback from thoracic chordotonal organs, which are known to be activated rhythmically during flight, contributes to the differential activation of efferent DUM neurones observed during flight.
Collapse
Affiliation(s)
- OT Morris
- Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK, Division of Neurobiology, University of Arizona, Tucson, AZ 85721, USA and Institut fur Zoologie, Universitat Leipzig, Talstrasse 33, D-04103 L
| | | | | |
Collapse
|
10
|
Abstract
Biogenic amines are important neuroactive molecules of the central nervous system (CNS) of several insect species. Serotonin (5HT), dopamine (DA), histamine (HA), and octopamine (OA) are the amines which have been extensively studied in Drosophila melanogaster. Each one of the four aminergic neuronal systems exhibits a stereotypic pattern of a small number of neurons that are widely distributed in the fly CNS. In this review, histochemical and immunocytochemical data on the distribution of the amine neurons in the larval and adult nervous system, are summarized. The majority of DA and 5HT neurons are interneurons, most of which are found in bilateral clusters. 5HT innervation is found in the feeding apparatus as well as in the endocrine organ of the larva, the ring gland. The octopaminergic neuronal population consists of both interneurons and efferent neurons. In the larval CNS all OA immunoreactive somata are localized in the midline of the ventral ganglion while in the adult CNS both unpaired neurons and bilateral clusters of immunoreactive cells are observed. One target of OA innervation is the abdominal muscles of the larval body wall where OA immunoreactivity is associated with the type II boutons in the axonal terminals. Histamine is mainly found in all photoreceptor cells where it is considered to be the major neurotransmitter molecule, and in specific mechanosensory neurons of the peripheral nervous system. Similarities between specific aminergic neurons and innervation sites in Drosophila and in other insect species are discussed. In addition, studies on the development and differentiation of 5HT and DA neurons are reviewed and data on the localization of 5HT, DA, and OA receptors are included as well. Finally, an overview on the isolation of the genes and the mutations in the amine biosynthetic pathways is presented and the implications of the molecular genetic approach in Drosophila are discussed.
Collapse
Affiliation(s)
- M Monastirioti
- Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology-Hellas (FORTH), Heraklion, Greece.
| |
Collapse
|
11
|
Johnston RM, Consoulas C, Levine RB. Patterned activation of unpaired median neurons during fictive crawling in manduca sexta larvae. J Exp Biol 1999; 202 (Pt 2):103-13. [PMID: 9851900 DOI: 10.1242/jeb.202.2.103] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The unpaired median neurons are common to the segmental ganglia of many insects. Although some of the functional consequences of their activation, among them the release of octopamine to modulate muscle contraction, have been described, less is understood about how and when these neurons are recruited during movement. The present study demonstrates that peripherally projecting unpaired median neurons in the abdominal and thoracic ganglia of the larval tobacco hornworm Manduca sexta are recruited rhythmically during the fictive crawling motor activity that is produced by the isolated central nervous system in response to pilocarpine. Regardless of the muscles to which they project, the efferent unpaired median neurons in all segmental ganglia are depolarized together during the phase of the crawling cycle when the thoracic leg levator motoneurons are active. During fictive crawling, therefore, the unpaired median neurons are not necessarily active in synchrony with the muscles to which they project. The rhythmical synaptic drive of the efferent unpaired median neurons is derived, at least in part, from a source within the subesophageal ganglion, even when the motor pattern is evoked by exposing only the more posterior ganglia to pilocarpine. In pairwise intracellular recordings from unpaired median neurons in different ganglia, prominent excitatory postsynaptic potentials, which occur with an anterior-to-posterior delay in both neurons, are seen to underlie the rhythmic depolarizations. One model consistent with these findings is that one or more neurons within the subesophageal ganglion, which project posteriorly to the segmental ganglia and ordinarily provide unpatterned synaptic inputs to all efferent unpaired median neurons, become rhythmically active during fictive crawling in response to ascending information from the segmental pattern-generating network.
Collapse
Affiliation(s)
- RM Johnston
- Division of Neurobiology, University of Arizona, Tucson, AZ 85721, USA.
| | | | | |
Collapse
|
12
|
Abstract
Neural messengers affect Drosophila heart rate. Serotonin increases larval, pupal, and adult heart rate. Octopamine and dopamine are inactive in larva, decrease pupal rate, and increase adult heart rate. Acetylcholine and nicotine decrease larval and pupal heart rate, while acetylcholine decreases and nicotine increases adult heart rate. Muscarine decreases pupal heart rate, but is inactive in larva and adult. GABA is inactive in larva and adult, but decreases pupal heart rate. Glutamate is inactive in larva and pupa, but decreases adult heart rate. Proctolin decreases heart rate in all three stages. Caffeine acts only to decrease adult heart rate.
Collapse
Affiliation(s)
- E Zornik
- Biological Chemistry Department, The University of Michigan, Ann Arbor 48109-1048, USA
| | | | | |
Collapse
|
13
|
Sinakevitch IG, Geffard M, Pelhate M, Lapied B. Anatomy and targets of Dorsal Unpaired Median neurones in the Terminal Abdominal Ganglion of the male cockroach Periplaneta americana L. J Comp Neurol 1996; 367:147-63. [PMID: 8867288 DOI: 10.1002/(sici)1096-9861(19960325)367:1<147::aid-cne9>3.0.co;2-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The morphology of the Dorsal Unpaired Median (DUM) neurones in the Terminal Abdominal Ganglion (TAG) of the adult male cockroach Periplaneta americana were described based on wholemount preparations and paraffin sections and by using anterograde and retrograde cobalt mapping, octopamine-like immunohistochemistry, and double immunofluorescence technique with both conjugated gamma-aminobutyric acid (GABA) and octopamine antisera. Among 60 +/- 6 neurones with large somata (diameter 40 to 60 microns) on the dorsal midline surface of the TAG that were stained with toluidine blue, about 36 efferent DUM neurones exhibited octopamine-like immunoreactivity. The DUM neurones were arranged in three clusters (anterior, median and posterior) corresponding to the 7th-11th abdominal ganglia of the fused TAG. Anterior efferent DUM neurones with one, two, and four pairs of lateral neurites entered segmental nerves VIIB; VIIB and phallic nerves; IXB and phallic nerves; VIIIA, IXA, X, and IX, respectively. Three octopamine-like immunoreactive DUM neurones innervating heart chambers via segmental nerves (VIIA, VIIIA, and IXA) in the last abdominal segments occurred within abdominal ganglia 7, 8, and 9. Together with octopamine-like immunoreactive efferent DUM neurones, GABA-like immunoreactive dorsal midline neurones with small somata (10 to 20 microns) also occurred within the median group. The spatial distribution of DUM neurones in the TAG suggested that they had their origins in the median neuroblast, as for DUM neurones in the grasshopper.
Collapse
Affiliation(s)
- I G Sinakevitch
- Laboratoire de Neurophysiologie, CNRS ERS 108, Université d'Angers, France
| | | | | | | |
Collapse
|
14
|
Pflüger HJ, Watson AH. GABA and glutamate-like immunoreactivity at synapses received by dorsal unpaired median neurones in the abdominal nerve cord of the locust. Cell Tissue Res 1995; 280:325-33. [PMID: 7781030 DOI: 10.1007/bf00307805] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Dorsal unpaired median (DUM) neurones in the abdominal ganglia of the locust were impaled with microelectrodes and some were injected intracellularly with horseradish peroxidase so that their synapses could be identified in the electron microscope. Simultaneous recordings from DUM neurones in different abdominal ganglia revealed that they received common postsynaptic potentials from descending interneurones. Post-embedding immunocytochemistry using antibodies against GABA and glutamate was carried out on ganglia containing HRP-stained neurones. GABA-like immunoreactivity was found in 39% (n = 82) of processes presynaptic to abdominal DUM neurones and glutamate-like immunoreactivity in 21% (n = 42) of presynaptic processes. Output synapses from the DUM neurites were rarely observed within the neuropile. Structures resembling presynaptic dense bars but not associated with synaptic vesicles, were seen in some large diameter neurites.
Collapse
Affiliation(s)
- H J Pflüger
- Institut für Neurobiologie, Freie Universität, Berlin, Germany
| | | |
Collapse
|
15
|
Stevenson PA, Spörhase-Eichmann U. Localization of octopaminergic neurones in insects. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART A, PHYSIOLOGY 1995; 110:203-15. [PMID: 7712064 DOI: 10.1016/0300-9629(94)00152-j] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This paper reviews data on the localization of octopaminergic neurons revealed by immunocytochemistry in insects, primarily the locusts Schistocerca gregaria and Locusta migratoria, cricket Gryllus bimaculatus, and cockroach Periplaneta americana. Supporting evidence for their octopaminergic nature is mentioned where available. In orthopteran ventral ganglia, the major classes of octopamine-like immunoreactive (-LI) neurones include: (1) efferent dorsal and ventral unpaired median (DUM, VUM) neurones; (2) several intersegmentally projecting DUM interneurones in the suboesophageal ganglion; other DUM interneurones are probably GABAergic; (3) a pair of anterior median cells in the prothoracic ganglion; (4) a single pair of ventral cells in most thoracic and some other ganglia; these appear to be plurisegmentally projecting interneurones. Eight categories of octopamine-LI neurones occur in the orthopteran brain. The basic projections of three types are described here: one class project to the optic lobes to form wide field projections. Another type descends to cross into the tritocerebral commissure and may invade the contralateral brain hemisphere. A further class is the median neurosecretory cells with axons in the nervi corpori cardiaci I. Available data for the honey bee Apis mellifera and moth Manduca sexta indicate that the octopamine-LI cell types found in orthopterans also occur in holometabolous insects. Immunocytochemical evidence suggests that some octopaminergic DUM cells contain an FMRFamide-related peptide and the amino acid taurine as putative cotransmitters.
Collapse
Affiliation(s)
- P A Stevenson
- Freie Universität Berlin, Institut für Neurobiologie, Germany
| | | |
Collapse
|