Fine Structural Study of the Abdominal Muscle Receptor Organs of the Crayfish (Procambarus clarkii)—Morphometrical Analysis of Synaptic Vesicles

1981 ◽  
Keyword(s):  
Structural Study ◽  
Synaptic Vesicles ◽  
Procambarus Clarkii ◽  
Abdominal Muscle ◽  
Muscle Receptor ◽  
Morphometrical Analysis

scholarly journals Abdominal postural motor responses initiated by the muscle receptor organ in lobster depend upon centrally generated motor activity

1992 ◽  
Vol 162 (1) ◽  
pp. 167-183
Author(s):  
S. C. Sukhdeo ◽  
C. H. Page
Keyword(s):  
Motor Activity ◽  
Motor Neurons ◽  
Procambarus Clarkii ◽  
Homarus Americanus ◽  
Abdominal Muscle ◽  
Sensory Response ◽  
Reflex Responses ◽  
Muscle Receptor ◽  
Postural Reflex ◽  
Receptor Organ

1. Stretch stimulation of the abdominal muscle receptor organ of the lobster Homarus americanus initiated spike discharge of its tonic sensory neuron (SR1). This sensory response evoked a series of tonic postural reflex responses in the motor neurons that innervate the superficial extensor and flexor muscles of the abdominal postural system. The type of motor response depended on whether a flexion or extension pattern of spontaneous activity was being generated by the postural efferents. Spontaneous shifts between these centrally generated motor activities completely changed the SR1-evoked reflex responses. 2. During spontaneous centrally initiated flexion activity, tonic SR1 neuron discharge elicited an assistance response that included excitation of a medium-sized flexor excitor (f3) and the peripheral extensor inhibitor (e5), and inhibition of at least one extensor excitor. Neither the other flexor excitors nor the peripheral flexor inhibitor (f5) were affected by SR1 excitation. 3. During spontaneous centrally initiated extension activity, SR1 activity elicited a response that included excitation of the extensor excitors and the flexor peripheral inhibitor (f5) only, f3 and e5 spontaneous activities were unchanged. This response was a resistance reflex, since SR1 discharge normally resulted from an imposed abdominal flexion. 4. The SR1-initiated control of postural motor activity in lobster differs from previously published results in the crayfish Procambarus clarkii.

The Lateral Giant Fiber to Motor Giant Fiber Synapse in Crayfish

1972 ◽  
Vol 30 ◽  
pp. 170-171
Author(s):  
Charles A. Stirling
Keyword(s):  
Synaptic Vesicles ◽  
Procambarus Clarkii ◽  
Synaptic Contact ◽  
Giant Fiber ◽  
Synaptic Junctions

The lateral giant (LG) to motor giant (MoG) synapses in crayfish (Procambarus clarkii) abdominal ganglia are the classic electrotonic synapses. They have previously been described as having synaptic vesicles and as having them on both the pre- and postsynaptic sides of symmetrical synaptic junctions. This positioning of vesicles would make these very atypical synapses, but in the present work on the crayfish Astacus pallipes the motor giant has never been found to contain any type of vesicle at its synapses with the lateral giant fiber.The lateral to motor giant fiber synapses all occur on short branches off the main giant fibers. Closely associated with these giant fiber synapses are two small presynaptic nerves which make synaptic contact with both of the giant fibers and with their small branches.

Cloning and characterization of sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA) from crayfish axial muscle. Sarco/Endoplasmic Reticulum Ca(2+)-ATPase

2000 ◽  
Vol 203 (22) ◽  
pp. 3411-3423 ◽  
Author(s):  
Z. Zhang ◽  
D. Chen ◽  
M.G. Wheatly
Keyword(s):  
Endoplasmic Reticulum ◽  
Amino Acid ◽  
Procambarus Clarkii ◽  
Muscle Growth ◽  
Abdominal Muscle ◽  
Northern Analysis ◽  
Specific Expression ◽  
Loop Region ◽  
Moulting Cycle

The discontinuous pattern of muscle growth during the moulting cycle of a freshwater crustacean (the crayfish Procambarus clarkii) was used as a model system to examine the regulation of the expression of Sarco/Endoplasmic Reticulum Ca(2+)-ATPase (SERCA). We describe the cloning, sequencing and characterization of a novel SERCA cDNA (3856 bp) obtained from crayfish axial abdominal muscle by reverse transcription/polymerase chain reaction (RT-PCR) followed by rapid amplification of cDNA ends (RACE). This complete sequence contains a 145 base pair (bp) noncoding region at the 5′ end, a 3006 bp open reading frame coding for 1002 amino acid residues with a molecular mass of 110 kDa and 705 bp of untranslated region at the 3′ end. This enzyme contains all the conserved domains found in ‘P’-type ATPases, and the hydropathy profile suggests a transmembrane organization typical of other SERCAs. It exhibits 80% amino acid identity with Drosophila melanogaster SERCA, 79% identity with Artemia franciscana SERCA, 72% identity with rabbit fast-twitch muscle neonatal isoform SERCA1b, 71% identity with slow-twitch muscle isoform SERCA2 and 67% identity with SERCA3. Sequence alignment revealed that regions anchoring the cytoplasmic domain in the membrane were highly conserved and that most differences were in the NH(2) terminus, the central loop region and the COOH terminus. Northern analysis of total RNA from crayfish tissues probed with the 460 bp fragment initially isolated showed four bands (7.6, 7.0, 5.8 and 4.5 kilobases) displaying tissue-specific expression. SERCA was most abundant in muscle (axial abdominal, cardiac and stomach), where it is involved in Ca(2+) resequestration during relaxation, and in eggs, where it may be implicated in early embryogenesis. The level of SERCA mRNA expression in axial abdominal muscle varied during the moulting cycle as determined by slot-blot analysis. SERCA expression was greatest during intermoult and decreased to approximately 50% of this level during pre- and postmoult. Patterns of gene expression for SERCA and other sarcomeric proteins during the crustacean moulting cycle may be regulated by ecdysteroids and/or mechanical stimulation.

Acute toxicity and accumulation of microcystin-leucine-arginine in the crayfish Procambarus clarkii (Girard, 1852)

Crustaceana ◽  
2015 ◽  
Vol 88 (4) ◽  
pp. 397-404 ◽  
Author(s):  
Zhenhua An ◽  
Zhenhua An ◽  
Longsheng Sun ◽  
Zhenhua An ◽  
Longsheng Sun ◽  
...  
Keyword(s):  
Survival Rate ◽  
Acute Toxicity ◽  
Procambarus Clarkii ◽  
Abdominal Muscle ◽  
Water Bodies ◽  
Lethal Concentration ◽  
Median Lethal Concentration ◽  
Toxicity Effect ◽  
Cyanobacteria Blooms

The aim of this study was to determine the acute toxicity effect and the accumulation of microcystin-leucine-arginine (MC-LR) on the crayfish Procambarus clarkii (Girard, 1852). Juvenile P. clarkii (5.47 ± 1.3 g) were cultured under 5 different MC-LR concentrations (0.3, 0.6, 1.2, 2.4, 4.8 mg/l), then the acute toxicity effect was observed. The median lethal concentration (LC50) of MC-LR on juvenile P. clarkii was 3.741 mg/l at 24 h, 1.494 mg/l at 48 h, 0.817 mg/l at 72 h and 0.567 mg/l at 96 h. Accumulation of MC-LR was measured in different organs of mature P. clarkii (58.7 ± 3.8 g) exposed to 0.3 mg/l MC-LR for 120 h. The detected MC-LR concentration decreased in the sequence: hepatopancreas > ovary > abdominal muscle > intestine. Hepatopancreas and ovary were found to be the main targets of the toxin. The results suggested that the MC-LR produced by cyanobacteria blooms could not only reduce the survival rate of juvenile P. clarkii but also affect the fecundity of mature crayfish. This research also provides a reference basis for the detection and assessment of the pollution of water bodies in P. clarkii culture.

The role of the muscle receptor organ in the control of abdominal extension in the crayfish, Cherax destructor

1995 ◽  
Vol 198 (11) ◽  
pp. 2253-2259 ◽  
Author(s):  
B Mccarthy ◽  
D Macmillan
Keyword(s):  
Constant Load ◽  
Abdominal Muscle ◽  
Muscle Receptor ◽  
Complete Extension ◽  
Cherax Destructor ◽  
Before And After ◽  
Error Detector ◽  
Receptor Organ ◽  
Servo Loop

A platform was lowered from beneath suspended crayfish, Cherax destructor, to evoke slow abdominal extension. The movements were filmed and the length between segments plotted as a function of time. Unlike abdominal flexion, which starts posteriorly and progresses anteriorly, extension occurs at all joints simultaneously. Although the duration of extension varied from trial to trial for an individual, the movement was organised in a stereotyped manner: the abdomen achieved a consistent position for any given proportion of the time for complete extension. We examined the role of the abdominal muscle receptor organs (MROs) in extension by cutting the nerves of selected MROs to abolish their input. The extension movement was measured before and after nerve section for animals with either unloaded or loaded abdomens. Removal of MRO input had no significant effect on extension of the unloaded abdomen. In animals with a loaded abdomen, the extension at joints spanned by sectioned MROs was slowed, whereas that at joints with intact MROs was not. The findings are consistent with the hypothesis that the MRO is an error detector in a servo-loop controlling abdominal position. The results provide the first demonstration that this load-compensating reflex loop operates during naturally evoked extension of the abdomen under constant load.

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