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 ◽  
...  

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.

1978 ◽  
Vol 202 (1147) ◽  
pp. 307-311 ◽  

Development of the oöcytes beyond the resting stage to maturity in mosquitoes is triggered by an egg development neurosecretory hormone from the brain. This hormone is produced by the medial neurosecretory cells of the pars intercerebralis, and in anautogenous species is stored in the corpus cardiacum until a blood-meal is taken. Removal of the head of the mosquito Aedes aegypti (L.), shortly after completion of a blood-meal, has previously been shown not only to prevent oöcyte maturation, but also to result in early elimination of the blood-meal. The work described in this paper shows that it is a factor originating in the medial neuro­-secretory cells, presumably egg development neurosecretory hormone, which is essential if the blood-meal is to be retained in the mid-gut until the oöcytes are nearing maturity.


Development ◽  
1960 ◽  
Vol 8 (2) ◽  
pp. 112-118
Author(s):  
R. B. Clark ◽  
D. G. Bonney

Hubl (1956) demonstrated that if the supra-oesophageal ganglion of lumbricid oligochaetes is removed at the time of amputation of a number of posterior segments, caudal regeneration is totally inhibited, but if the ganglion is not removed until 24–48 hours after amputation of the posterior segments, regeneration proceeds at the normal rate. A comparable phenomenon may occur in nereid polychaetes. Removal of the prostomium (Casanova, 1955) or, more precisely, of the supra-oesophageal ganglion (Durchon, 1956), retards regeneration but does not prevent it, but as these experiments were performed. On the day following amputation of the posterior segments it is still not certain whether the brain of Nereis is, at any stage, essential for posterior regeneration as it clearly is in lumbricids. In his investigation of Lumbricus and Allolobophora, Hubl (1956) found that neurosecretory cells in the supra-oesophageal ganglion, the b-cells, showed intense secretory activity as soon as the worm was injured and the ventral nerve-cord damaged.


1963 ◽  
Vol 40 (3) ◽  
pp. 517-530
Author(s):  
KINSAKU HASEGAWA

1. The action of the diapause hormone has been studied by injecting extracts of the heads of male moths or of the brain-suboesophageal ganglion complexes of pupae into pupae expected to produce non-diapause eggs. 2. The effect of the injection of hormone upon young oocytes is to make them develop into diapause eggs. Older oocytes, which have already acquired non-diapause characters, are not affected. 3. The hormone is almost completely inactivated when injected on the day of pupation. The hormone is most effective when injected into pupae 2-3 days old, at which stage the ovarioles have started to grow vigorously. It is ineffective 1-2 days before adult emergence, by which time all the oocytes have acquired non-diapause characters. 4. The hormone is inactivated in all pupae irrespective of whether they are destined to produce diapause eggs or non-diapause eggs. Inactivation of diapause hormone (in contrast to that of juvenile hormone) is partially relieved by exposure to low temperature or by simultaneous injection of indian ink. 5. The extracts prepared as in (1) above do not serve as a stimulant for the brain causing the suboesophageal ganglion to produce diapause hormone. The action of the extract faithfully reflects the function of the diapause hormone which originates in the suboesophageal ganglion.


1978 ◽  
Vol 56 (9) ◽  
pp. 1988-1992 ◽  
Author(s):  
M. Grossman ◽  
K. G. Davey

An analysis of the intensity of staining of the corpus cardiacum and of the neurosecretorty cells of the pars intercerebralis in 3-day-old fed or fasting adult male tsetse has revealed two periods of apparent release of neurosecretion. In fed males, stainable neurosecretion disappears from 14 of the 20 recognizable neurosecretory cells within 10 min of the termination of feeding. There is always less neurosecretory material in the corpora cardiaca of fed males. Secondly, there is an indication of a depletion of material from the cardiaca of both fed and fasted males at about 1700 hours EST.


2016 ◽  
Vol 300 (2) ◽  
pp. 415-424
Author(s):  
Shun Wang ◽  
Zhe Dong ◽  
Shen Li ◽  
Haotian Yin ◽  
Zhifu Zhao ◽  
...  

1979 ◽  
Vol 205 (1160) ◽  
pp. 411-421 ◽  

Most female mosquitoes require a blood-meal in order to produce mature oöcytes. An egg development neurosecretory hormone (EDNH), which is produced in the medial neurosecretory cells (m. n. c.) of the brain and stored in the corpus cardiacum, is released into the haemolymph following the ingestion of blood and is essential for the promotion of ovarian development to maturity. It has been shown that a factor from the m. n. c., presumably EDNH, is necessary if the blood-meal is to be retained in the mid-gut until the oöcytes approach maturity. The present paper shows that retention is not a direct result of the action of EDNH, but is dependent on the ovaries and may well involve ecdysone. Removal of the ovaries before a blood-meal leads to early haem-defaecation, but delay can be restored by injection of ecdysterone. Sub-threshold feeders and mosquitoes decapitated immediately after the intake of blood, each of which would be expected to eliminate the blood-meal early, also show a delay in the onset of haem-defaecation when injected with ecdysterone. Further, both in ovariectomized insects and sub-threshold feeders the time of onset of haem-defaecation is associated with the dose of ecdysterone given.


Author(s):  
D. Benzid ◽  
C. Morris ◽  
R.-M. Barthélémy

This investigation constitutes the first study of the serotoninergic nervous system in calanoid copepods (crustaceans). Serotonin (5-HT), a neurotransmitter which plays a part in many biological processes, has been detected by immunofluorescence in the brain, the circumoesophageal collar and the ventral nerve cord of the marine species Centropages typicus.


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