Morphology and histology of the cephalic endocrine glands of the damselfly, Coenagrion angulatum Walker (Zygoptera: Odonata)

1969 ◽  
Vol 47 (6) ◽  
pp. 1187-1192
Author(s):  
C. Gillott
Keyword(s):  
Sexual Maturation ◽  
Adult Life ◽  
Secretory Activity ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Single Pair ◽  
General Shape ◽  
Corpora Cardiaca ◽  
Ventral Glands ◽  
The Brain

In Coenagrion angulatum Walk. there is a single group of neurosecretory cells, median in position, on each side of the brain. The A- and B-type cells are intermingled within each group and their axons form a single pair of nerves to the corpora cardiaca. No pattern of secretory activity is discernible in the B cells. The A cells of mature nymphs and newly emerged adults are loaded with fuchsinophilic droplets but the amount of stainable material decreases as sexual maturation proceeds. A corresponding change in the location and amount of fuchsinophilic material takes place in the corpora cardiaca. In the mature nymph and young adult there is much material distributed throughout the gland. During sexual maturation it becomes less in quantity and restricted to a position adjacent to the aorta wall. A pair of stout, strongly fuchsinophilic nerves leaves the anterior end of the corpora cardiaca and passes ventrolaterally. These bypass the corpora allata and enter the thorax. Their point of termination has not been determined in this study. The corpora allata are small, roundish-oval bodies in the mature juvenile and newly emerged adult damselfly. While retaining their general shape they increase in volume several fold as sexual maturation takes place. The ventral glands are large, lobular structures in mature nymphs. Immediately after emergence they shrink and their cells become pycnotic. Generally by the fourth day of adult life they have disappeared. The results of this study are discussed in relation to those of other authors for the Odonata.

Activity of the Corpora Allata during Pupal Diapause in Mimas tiliae (Lepidoptera)

1958 ◽  
Vol s3-99 (46) ◽  
pp. 171-180
Author(s):  
K.C. HIGHNAM
Keyword(s):  
Low Temperature ◽  
Oxygen Uptake ◽  
Fat Body ◽  
Neurosecretory Cells ◽  
Corpora Allata ◽  
Histological Observation ◽  
Corpora Cardiaca ◽  
Pupal Diapause ◽  
The Brain

Histological observation indicates that the corpora allata of Mimas tiliae are secretory during pupal diapause, but become inactive by the end of the low-temperature period which terminates diapause. Removal of the corpora allata, together with the corpora cardiaca, from the diapausing pupa increases the thickness of the hypodermis and decreases the number of fat-body inclusions (compared with operated controls), but does not result in any visible signs of diapause break. The oxygen uptake of the pupa increases by about 60% by the end of the low-temperature period, compared with the diapausing pupa. It is probable that the corpora allata play some part in the maintenance of diapause, possibly by exercising some control over the fat-body metabolism. This role is subservient to that of the neurosecretory cells in the brain, together with their associated corpora cardiaca.

THE NEUROENDOCRINE ORGANS OF LARVAE OF NEODIPRION LECONTEI, N. SWAINEI, AND DIPRION HERCYNIAE (HYMENOPTERA: DIPRIONIDAE)

1973 ◽  
Vol 105 (5) ◽  
pp. 725-731 ◽  
Author(s):  
C. F. Hinks
Keyword(s):  
Neurosecretory Cells ◽  
Corpus Allatum ◽  
Single Pair ◽  
Corpora Cardiaca ◽  
Neodiprion Lecontei ◽  
Lateral Organs ◽  
Segmental Nerve ◽  
Endocrine Organs ◽  
Neuroendocrine Organs ◽  
The Brain

AbstractLarvae and eonymphs of the diprionid sawflies Neodiprion lecontei (Fitch), Neodiprion swainei Midd., and Diprion hercyniae (Htg.) were dissected and stained to demonstrate the nervous system and endocrine organs. Morphologically and anatomically the endocrine organs in both larvae and eonymphs of all three species are very similar. The cephalic structures comprise lateral and medial neurosecretory cells in the brain which discharge their secretions through a single pair of nerves (NCC) to the corpora cardiaca. The NCC divide before they enter the corpora cardiaca sending a branch to the corresponding corpus allatum. No other nervous connections with these organs are apparent.Paired neurohaemal organs occur in each thoracic segment, forming distinct dilations on slender nerves arising from the ventral cord connectives. They receive secretions from groups of lateral neurosecretory cells in the thoracic ganglia.Each abdominal ganglion has three neurohaemal organs associated with it, a single small spherical structure antero-medially, and paired lateral organs of a diffuse structure, overlying the base of each segmental nerve. They are less conspicuous than the thoracic organs and have different staining properties.

Activity of the Brain/Corpora Cardiaca System during Pupal Diapause ‘Break’ in Mimas tiliae (Lepidoptera)

1958 ◽  
Vol s3-99 (45) ◽  
pp. 73-88
Author(s):  
K. C. HIGHNAM
Keyword(s):  
Low Temperature ◽  
Secretory Activity ◽  
Neurosecretory Cells ◽  
Corpora Cardiaca ◽  
Endocrine Organs ◽  
Pupal Diapause ◽  
Diapause Development ◽  
Histological Results ◽  
Further Development ◽  
The Brain

Pupal diapause in Mimas tiliae can be terminated by keeping the pupa for at least 4 weeks at 3° C. The adult emerges about 15 days after transfer to 25° C. Histological examination shows that the neurosecretory cells in the brain are inactive in the diapausing pupa, but they elaborate intracellular material during the first 3 weeks at 3° C. The material is passed to the corpora cardiaca. The neurosecretory cells are again inactive by the end of the low-temperature period. The brain/cardiaca system shows little sign of secretory activity during the subsequent period at 25° C. The corpora cardiaca undergo phagocytosis and reorganization during this time. This suggests that conditions for further development are established by the end of the low-temperature period. This hypothesis is supported by the fact that development of the non-endocrine organs begins immediately the pupa is transferred to 25° C after 4 weeks at 3° C. Extirpation and implantation experiments involving the brain, with and without its associated corpora cardiaca, support the histological results, indicating that the brain is necessary for diapause development at 3° C and that the corpora cardiaca are involved in the release of the brain factor.

scholarly journals Peptidomic Analysis of the Brain and Corpora Cardiaca-Corpora Allata Complex in the Bombyx mori

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Xiaoguang Liu ◽  
Xia Ning ◽  
Yan Zhang ◽  
Wenfeng Chen ◽  
Zhangwu Zhao ◽  
...  
Keyword(s):  
Bombyx Mori ◽  
Developmental Stages ◽  
Larval Instar ◽  
Corpora Allata ◽  
Corpora Cardiaca ◽  
Rp Hplc ◽  
Transcriptome Database ◽  
Peptidomic Analysis ◽  
Peptide Profiles ◽  
The Brain

The silkworm, Bombyx mori, is an important economic insect for silk production. However, many of the mature peptides relevant to its various life stages remain unknown. Using RP-HPLC, MALDI-TOF MS, and previously identified peptides from B. mori and other insects in the transcriptome database, we created peptide profiles showing a total of 6 ion masses that could be assigned to peptides in eggs, including one previously unidentified peptide. A further 49 peptides were assigned to larval brains. 17 new mature peptides were identified in isolated masses. 39 peptides were found in pupal brains with 8 unidentified peptides. 48 were found in adult brains with 12 unidentified peptides. These new unidentified peptides showed highly significant matches in all MS analysis. These matches were then searched against the National Center for Biotechnology Information (NCBI) database to provide new annotations for these mature peptides. In total, 59 mature peptides in 19 categories were found in the brains of silkworms at the larval, pupal, and adult stages. These results demonstrate that peptidomic variation across different developmental stages can be dramatic. Moreover, the corpora cardiaca-corpora allata (CC-CA) complex was examined during the fifth larval instar. A total of 41 ion masses were assigned to peptides.

Studies on the physiology of a shrimp, Metapenaeus sp. (Crustacea: Decapoda: Penaeidae). II. Endocrines and control of moulting

1965 ◽  
Vol 16 (1) ◽  
pp. 1 ◽  
Author(s):  
W Dall
Keyword(s):  
Neurosecretory Cells ◽  
Endocrine Glands ◽  
Extrinsic Factors ◽  
Eyestalk Ablation ◽  
Longitudinal Strip ◽  
Different Seasons ◽  
Ventral Glands ◽  
And Control ◽  
The Brain ◽  
Ventral Gland

Eyestalk ganglionic neurosecretory endocrine glands, the sinus gland, and sensory-pore organ are described and figured. The thoracic gland was found to be a narrow longitudinal strip of epitheloid tissue immediately inside the dorsal cuticle of the anterior branchial chamber. Neurosecretory cells were present in the brain and thoracic ganglia, and post-commissural organs were identified. Moulting was erratic under laboratory conditions and tended to be arrested at an early premoult stage. Moulting could not be induced in intact, nor accelerated in eyestalkless animals by injections of sensory-pore-complex extracts. Ventral glands (Y-organs) and ventral gland extracts from two species of crab donor at different seasons and from eyestalkless donors were also without effect. Eyestalk ablation induced moulting, but the response was relatively slow and erratic. It is concluded that there is little evidence for the existence of a specific moult-accelerating hormone in this species, that morphogenetic hormone is ineffective unless extrinsic factors and nutritional state are optimal, and that moult-inhibiting hormone is largely produced within the eyestalk.

Asymmetry in hormone biosynthesis by insect endocrine glands

1977 ◽  
Vol 55 (9) ◽  
pp. 1509-1514 ◽  
Author(s):  
Stephen S. Tobe
Keyword(s):  
Schistocerca Gregaria ◽  
Adult Life ◽  
Relative Activity ◽  
Corpora Allata ◽  
Endocrine Function ◽  
Endocrine Glands ◽  
Hormone Biosynthesis ◽  
Left And Right ◽  
Absolute Quantity ◽  
The Brain

The corpora allata (CA) of the desert locust Schistocerca gregaria are paired endocrine glands known to synthesize juvenile hormone (JH). The ability of individual members of the pair to synthesize JH has been examined between days 7 and 14 of adult life. Left and right glands in an individual animal can make different quantities of JH (up to 1000: 1), indicating that it cannot be assumed that endocrine glands in any given animal are of equal endocrinological activity. This asymmetry in endocrine function appears to be randomly distributed and thus the relative activity of members of the pair cannot be predicted. The asymmetry does not appear to be related to either the total quantity of JH synthesized or to the age of the animals. It is significant that no matter which member of the pair is more active, the absolute quantity of hormone synthesized by the CA of different animals of the same age is similar. The factors which regulate the endocrine asymmetry are not known but feedback loops between the brain and CA are implied. The functional significance of asymmetry may be related to a cyclical alternation in synthesis of JH by the members of the pair.

Projection of FMRFamide-like neuropeptide-producing neurosecretory cells from silkworm brain into ventral nerve cord and retrocerebral complex

2012 ◽  
Vol 144 (3) ◽  
pp. 458-466 ◽  
Author(s):  
Bo Yong Kim ◽  
Hwa Young Song ◽  
Mi Young Kim ◽  
Pil Don Kang ◽  
Min Ho Cha ◽  
...  
Keyword(s):  
Juvenile Hormone ◽  
Bombyx Mori ◽  
Nerve Cord ◽  
Ventral Nerve Cord ◽  
Neurosecretory Cells ◽  
Single Pair ◽  
Corpus Cardiacum ◽  
Pars Intercerebralis ◽  
Median Region ◽  
The Brain

AbstractUsing immunostaining methodology, we traced the axonal projection of FMRFamide (Phe-Met-Arg-Phe-NH2)-like immunoreactive (LI) medial neurosecretory cells (MNCs) and lateral neurosecretory cells (LNCs) from the brain into the ventral nerve cord (VNC) and retrocerebral complex in Bombyx mori (L.) (Lepidoptera: Bombycidae). Of the seven pairs of FMRFamide-LI MNCs, one pair extended its axons from the brain pars intercerebralis into the VNC ipsilateral connective where they appeared to terminate. The axons of the remaining MNCs ran through decussation in the brain median region and contralateral nervi corporis cardiaci (NCC) I out of the brain, and eventually innervated the contralateral corpus cardiacum (CC). Axons from the single pair of FMRFamide-LI LNCs projected into the ipsilateral NCC II fused with NCC I without decussation in the brain, and finally terminated in the CC. These results suggest that transport of the FMRFamide-like neuropeptide from may be related to the modulation of functions such as gut contraction in MNCs terminating in the VNC, and regulation of production and/or secretion of specific hormones such as juvenile hormone in MNCs and LNCs terminating in the CC.

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