Morphology and physiology of motor neurons innervating labral muscles of locusta migratoria [Elektronische Ressource] / Abid Mahmood Alvi

Abid

Sujets

• Biologie

Informations

• Publié par: rheinisch-westfalischen_technischen_hochschule_-rwth-_aachen
• Publié le: 01 janvier 2011
• Nombre de lectures: 46
• Poids de l'ouvrage: 7 Mo

Extrait

Morphology and Physiology of Motor Neurons
Innervating Labral Muscles of Locusta migratoria





Von der Fakultät für Mathematik, Informatik und Naturwissenschaften
der RWTH Aachen zur Erlangung des akademischen Grades
eines Doktors der Naturwissenschaften genehmigte
Dissertation




vorgelegt von

M.Sc. Agri. Entomology
Abid Mahmood Alvi
aus
Layyah, Pakistan




Berichter:

Herr Universitätprofessor Dr. Peter Bräunig
Herr Privatdozent Dr. Rudolf Loesel



Tag der mündlichen Prüfung: 08.06.2011



Diese Dissertation ist auf den Internetseiten der Hochschulbibliothek online
verfügbar




Table of Contents
Table of Contents:
1. Introduction: ................................................................... 1
1.1. Insect head segmentation: ......................................................................................1
1.2. Nature of labrum: ...................................................................................................6
1.3. Segmental affiliation of the labrum:.......................................................................7
1.4. Aims of Thesis: ......................................................................................................8
2. Materials and Methods:................................................ 11
2.1. Animals: ...............................................................................................................11
2.2. Locust ringer solution:..........................................................................................11
2.3. Retrograde labelling of neurons: ..........................................................................11
2.3.1. Dissection:.....................................................................................................12
2.3.2. Neurobiotin staining:.....................................................................................12
2.3.3. Nickel chloride staining: ...............................................................................13
2.3.4. Photography and Microscopy: ......................................................................13
2.4. Electrophysiology:................................................................................................13
2.4.1. Dissection:.....................................................................................................14
2.4.2. Intracellular recording:..................................................................................14
2.4.2.1. Enzyme treatment: .................................................................................14
2.4.2.2. Glass microelectrode: ............................................................................15
2.4.2.3. Glass micro electrode mounting: ...........................................................15
2.4.2.4. Indifferent electrode:..............................................................................15
2.4.2.5. Amplifier:...............................................................................................15
2.4.2.6. Probing of neurons:................................................................................15
2.4.2.7. Data acquisition: ....................................................................................16
2.4.2.8. Identification of neurons:.......................................................................16
2.4.2.9. Orthodromic stimulation:.......................................................................16
2.4.2.10. Antidromic stimulation: ........................................................................16
2.4.3. Intracellular staining: ....................................................................................17
2.4.4. Data analysis: ................................................................................................17
3. Results........................................................................... 19
3.1. Morphology of insect labrum:..............................................................................19
3.2. Musculature of labrum: ........................................................................................19
3.2.1. Compressor muscles of labrum (M1): ..........................................................20
3.2.2. Anterior retractor muscles of labrum (M2):..................................................21
3.2.3. Posterior retractor muscles of labrum (M3):.................................................21
3.2.4. Anterior dilator muscles of foregut (M38):...................................................21
3.3. Innervation of labral muscles: ..............................................................................21
3.3.1. Insect nervous system: ..................................................................................21
3.3.2. Branching pattern of frontal connective........................................................22
3.3.3. Innervation of compressor muscles of labrum (M1):....................................23
3.3.4. Innervation of anterior retractor muscles of labrum (M2): ...........................24
3.3.5. Innervation of posterior retractor muscles of labrum (M3) and anterior
dilator muscles of foregut (M38): ...............................................................................25
3.3.6. Peripheral neurosecretory cells: ....................................................................26
3.3.7. General motor innervation pattern of labral muscles:...................................26
3.4. Retrograde labelling of motor neurons innervating labral musculature:..............27
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3.4.1. Neurons innervating compressor muscles of labrum (M1): .........................27
3.4.2. Neurons innervating anterior retractor muscles of labrum (M2):.................27
3.4.2.1. Backfilling of M2-commissure:.............................................................27
3.4.2.2. Backfilling of motor nerve branch to M2:.............................................31
3.4.2.3. Backfilling of M2-commissure or motor nerve branch to M2 and
suboesophageal ganglion neurons: .........................................................................41
3.4.3. Neurons innervating posterior retractor muscles of labrum M3:..................41
3.4.3.1. Backfilling of motor nerve branch to M3:.............................................41
3.4.3.2. Direct backfilling of M3:.......................................................................46
3.4.4. Neurons innervating anterior dilator muscles of foregut (M38):..................47
3.4.5. Backfilling of M3 and M38 motor nerves together: .....................................51
3.4.6. Contralateral targets of suboesophageal neurons:.........................................57
3.5. Action of motor neurons innervating labral muscles: ..........................................59
3.5.1. Intracellular recording from anterior retractor muscles of labrum (M2): .....59
3.5.2. Intracellular recording from posterior retractor muscles of labrum (M3): ...60
3.5.3. Intracellular recording from ipsilateral M2 and M3: ....................................61
3.5.4. Intracellular recording from ipsilateral M3 and M38: ..................................62
3.6. Physiological properties of suboesophageal ganglion motor neurons: ................63
3.6.1. Simultaneous intracellular recording from fibers of M2, M3 and
suboesophageal ganglion motor neurons:...................................................................63
3.6.2. Simultaneous intracellular recording from fibers of M38 and SOG neuron:70
4. Discussion: ................................................................... 73
4.1. Innervation pattern of labral muscles:..................................................................73
4.2. Organization of motor neurons: ...........................................................................74
4.3. Neurosecretory and neuromodulatory innervation:..............................................77
4.4. Physiology of labral musculature:........................................................................78
4.5. Absence of inhibitory innervation:.......................................................................80
5. Conclusion: ................................................................... 83
5.1. Sequence of labral muscles: .................................................................................83
5.2. Innervation pattern: ..............................................................................................83
5.3. Appendage of intercalary segment:......................................................................84
6. Summary: ...................................................................... 87
7. References: ................................................................... 89
Acknowledgements ......................................................... 105
Curriculum Vitae .............................................................. 107


ii

Introduction
1. Introduction:
Multicellular life appeared in the Precambrian period and no lineage of animals is known
until the Cambrian (Morris, 1979, 1989, 1993, 2000). The lineages of animals are