Neurosecretion and shell regeneration in Helisoma duryi (Mollusca: Pulmonata)

1976 ◽  
Vol 54 (10) ◽  
pp. 1771-1778 ◽  
Author(s):  
R. M. Dillaman ◽  
A. S. M. Saleuddin ◽  
Gwyneth M. Jones
Keyword(s):  
Tissue Injury ◽  
Secretory Granules ◽  
Neurosecretory Cells ◽  
Neurosecretory Material ◽  
Positive Material ◽  
Helisoma Duryi ◽  
Cell Groups ◽  
Shell Regeneration ◽  
The Brain ◽  
Group 1

The distribution of cells that stain positively with paraldehyde fuchsin (PAF) in the brain of Helisoma duryi has been mapped. Two cell groups occur in the visceral ganglion, one of which (group 1) has been shown to contain electron-dense secretory granules resembling neurosecretory material. Backfilling experiments and serial sectioning show that group 1 cells send axons into the intestinal and left pallial nerves.PAF-positive material is depleted from group 1 cells between 24 and 48 h after shell removal and has reappeared by 72 h. PAF-positive material accumulates in the axons by 24 h and disappears by 48 h; shell regeneration is apparently complete within 15 days. Tissue injury alone or shell removal from a non-regenerating area does not cause depletion of stainable material in these cells. No change in stainability occurs in other PAF-positive cells in the brain during shell regeneration. It is suggested that this cycle of activity may indicate involvement of the group 1 neurosecretory cells in the control of shell regeneration.

Humoral Regulation of the Cerebral Neurosecretory System of Rhodnius Prolixus (Stal.) During Growth and Moulting

1973 ◽  
Vol 58 (1) ◽  
pp. 177-187
Author(s):  
C. G. H. STEEL
Keyword(s):  
Critical Period ◽  
Endocrine System ◽  
Feedback Regulation ◽  
Neurosecretory Cells ◽  
Corpus Allatum ◽  
Neurosecretory System ◽  
Neurosecretory Material ◽  
Before And After ◽  
Cytological Changes ◽  
The Brain

1. In normal fifth instar Rhodnius the cytological changes occurring in the medial neurosecretory cells (MNC) of the brain are very different before and after the ‘critical period’ for decapitation. 2. When a decapitated insect which has reached the ‘critical period’ (8 days after feeding) is joined in parabiosis to an insect with an intact cerebral endocrine system and which has not yet reached the ‘critical period’ (1 day after feeding) the MNC of the younger insect are induced to switch over from their normal sequence of cytological changes to those characteristic of the older insect. The induced changes do not occur in normal insects of the same age or in insects joined in parabiosis to others of the same age. 3. The nature of the changes indicates that release of stainable neurosecretory material is inhibited and its synthesis stimulated by the older insect. It is inferred that the haemolymph of insects which have reached the ‘critical period’ contains a factor which induces in the MNC an inhibition of release and a stimulation of synthesis. These are the events which occur in the MNC of normal insects at the critical period. 4. Considerable circumstantial evidence suggests that the factor is ecdysone. It may act either directly on the brain or on the corpus allatum. Its contribution to a feedback regulation of the endocrine system controlling growth and moulting is discussed.

The role of neurosecretion in the photoperiodic control of polymorphism in the aphid Megoura viciae

1977 ◽  
Vol 67 (1) ◽  
pp. 117-135
Author(s):  
C. G. Steel ◽  
A. D. Lees
Keyword(s):  
Neurosecretory Cells ◽  
Neurosecretory Material ◽  
Compound Eyes ◽  
Long Day ◽  
Group I ◽  
Megoura Viciae ◽  
Probable Site ◽  
I Cells ◽  
The Brain

The location of the photoperiodic mechanism controlling the production of the sexual and parthenogenetic morphs by apterous parents was examined by selectively injuring the brain with an R.F. microcautery. Lesions destroying the Group I neurosecretory cells (NSC) in the protocerebrum abolished the response to changed daylength. Extensive damage to other NSC Groups, to the compound eyes and optic lobes was without effect. It is concluded that the Group I NSC are the effectors, secreting a virginoparapromoting substance; in its absence only oviparae are produced. Areas slightly lateral to the group I NSC are also required for the long-day response, indicating that this is the probable site of the neuronal photoperiodic clock which regulates the release of neurosecretory material (NSM) from the Group I cells.

The brain structure and neurosecretory cells of noctuid moth Anadevidia peponis: Noctuidae

1990 ◽  
Vol 48 (3) ◽  
pp. 436-437
Author(s):  
M. Sato ◽  
Y. Ogawa ◽  
M. Sasaki ◽  
T. Matsuo
Keyword(s):  
Biological Clock ◽  
Virgin Female ◽  
Basic Structure ◽  
Fixed Time ◽  
Neurosecretory Cells ◽  
Nerve Cells ◽  
Noctuid Moth ◽  
The Right ◽  
20 Nm ◽  
The Brain

A virgin female of the noctuid moth, a kind of noctuidae that eats cucumis, etc. performs calling at a fixed time of each day, depending on the length of a day. The photoreceptors that induce this calling are located around the neurosecretory cells (NSC) in the central portion of the protocerebrum. Besides, it is considered that the female’s biological clock is located also in the cerebral lobe. In order to elucidate the calling and the function of the biological clock, it is necessary to clarify the basic structure of the brain. The observation results of 12 or 30 day-old noctuid moths showed that their brains are basically composed of an outer and an inner portion-neural lamella (about 2.5 μm) of collagen fibril and perineurium cells. Furthermore, nerve cells surround the cerebral lobes, in which NSCs, mushroom bodies, and central nerve cells, etc. are observed. The NSCs are large-sized (20 to 30 μm dia.) cells, which are located in the pons intercerebralis of the head section and at the rear of the mushroom body (two each on the right and left). Furthermore, the cells were classified into two types: one having many free ribosoms 15 to 20 nm in dia. and the other having granules 150 to 350 nm in dia. (Fig. 1).

HISTOMORPHOLOGICAL CHANGES IN THE BRAIN IN RELATION TO OVARIAN CYCLE OF FRESHWATER CRAB, BARYTELPHUSA CUNICULARIS

2017 ◽  
Vol 23 (1) ◽  
Author(s):  
C.A. JAWALE
Keyword(s):  
Staining Intensity ◽  
Neurosecretory Cells ◽  
Ovarian Cycle ◽  
Secretory Product ◽  
Freshwater Crab ◽  
Intensity Index ◽  
Cytoplasmic Material ◽  
Histomorphological Changes ◽  
Cyclic Changes ◽  
The Brain

Ovarian maturation by neurosecretory cells in the brain of freshwater crab, Barytelphusa cunicularis have been examined. The histological scrutiny of the brain of Barytelphusa cunicularis related with three types (A, B and C) of neurosecretory cells, which are classified on the basis of size, shape and tinctorial characters. All these types of cells marked annual cyclic changes of cytoplasmic material in association with ovarian cycle. The activity of these cells has been correlated with the ovarian cycle. They are distinguishable by their size, nature locations, shape, nucleus position, cell measure and the secretory product in the cytoplasm. The result indicates that the neurosecretory A, B and C cells of the brain seen involved in the process of mating ovulation. The neurosecretory materials staining intensity index of these cells is described.

scholarly journals Using electrodermal activity to validate multilevel pain stimulation in healthy volunteers evoked by thermal grills

2020 ◽  
Vol 319 (3) ◽  
pp. R366-R375
Author(s):  
Hugo F. Posada-Quintero ◽  
Youngsun Kong ◽  
Kimberly Nguyen ◽  
Cara Tran ◽  
Luke Beardslee ◽  
...  
Keyword(s):  
Tissue Injury ◽  
Electrodermal Activity ◽  
Pain Scale ◽  
Potential Harm ◽  
Electric Pulses ◽  
Stimulation Level ◽  
Highly Correlated ◽  
The Brain ◽  
Different Levels ◽  
Assessment Research

We have tested the feasibility of thermal grills, a harmless method to induce pain. The thermal grills consist of interlaced tubes that are set at cool or warm temperatures, creating a painful “illusion” (no tissue injury is caused) in the brain when the cool and warm stimuli are presented collectively. Advancement in objective pain assessment research is limited because the gold standard, the self-reporting pain scale, is highly subjective and only works for alert and cooperative patients. However, the main difficulty for pain studies is the potential harm caused to participants. We have recruited 23 subjects in whom we induced electric pulses and thermal grill (TG) stimulation. The TG effectively induced three different levels of pain, as evidenced by the visual analog scale (VAS) provided by the subjects after each stimulus. Furthermore, objective physiological measurements based on electrodermal activity showed a significant increase in levels as stimulation level increased. We found that VAS was highly correlated with the TG stimulation level. The TG stimulation safely elicited pain levels up to 9 out of 10. The TG stimulation allows for extending studies of pain to ranges of pain in which other stimuli are harmful.

Neurosecretory Cells in the Brain of the Larva of Lucilia caesar L.

Nature ◽  
1957 ◽  
Vol 179 (4553) ◽  
pp. 257-258 ◽  
Author(s):  
ALASTAIR FRASER
Keyword(s):  
Neurosecretory Cells ◽  
The Brain

Protective effect of Saccharomyces cerevisiae in Rattus norvegicus Ischemic Stroke Model

2021 ◽  
pp. 5785-5789
Author(s):  
Dedy Budi Kurniawan ◽  
Mokhamad Fahmi Rizki Syaban ◽  
Arinal Mufidah ◽  
Muhammad Unzila Rafsi Zulfikri ◽  
Wibi Riawan
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Ischemic Stroke ◽  
Brain Tissue ◽  
Tissue Injury ◽  
Intervention Group ◽  
Positive Control ◽  
Positive Control Group ◽  
Control Group ◽  
Hematopoietic Stem ◽  
The Brain

Stroke is one of the leading causes of morbidity and mortality in all ages. Ischemic stroke activates excitotoxic glutamate cascade leading to brain tissue injury. Saccharomyces cerevisiae is a unicellular yeast widely found in nature. S. cerevisiae is neuroprotective and able to increase the differentiation of hematopoietic stem cells (HSCs) into neuronal cells. it may increase levels of neuroprotectant BDNF in the brain tissue, therefore increase the protection of neurons. BDNF may prevent glutamate-driven excitotoxicity by reducing glutamate levels. This study uses a randomized post-test only controlled group design. In this in vivo study, rodent models of ischemic stroke were divided into five groups comprising of the negative control group, positive control group, intervention group 1 (18mg/kgBW), intervention group 2 (36mg/kgBW) and intervention group 3 (72 mg/kgBW). Groups treated with Saccharomyces cerevisiae extract showed significantly increased BDNF levels in the brain tissue, and the expression of the glutamate level was significantly reduced (P <0.05) compared to the positive control group. Thus Saccharomyces cerevisiae has a promising potential to become a therapy against ischemic stroke disease. however further research is needed regarding the efficacy and toxicity of Saccharomyces cerevisiae.

Attenuation of Haemodynamic Response to Placement of Mayfield Skull Pin Head Holder - Comparison of Dexmedetomidine Versus Propofol Infusion - A Randomized Interventional Trial Done in a Tertiary Centre in Central Kerala

2021 ◽  
Vol 8 (29) ◽  
pp. 2639-2643
Author(s):  
Sruthy Unni ◽  
Ranju Sebastian ◽  
Elizabeth Joseph ◽  
Remani Kelan Kamalakshi ◽  
Jamsheena Muthira Parambath
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Stress Response ◽  
Intracranial Pressure ◽  
Cerebral Perfusion ◽  
Perfusion Pressure ◽  
Neurosurgical Procedures ◽  
Sympathetic Nervous ◽  
The Brain ◽  
Group 1

BACKGROUND Anaesthesia for neurosurgery requires special considerations. The brain is enclosed in a rigid cranium, so the rise in intracranial pressure (ICP) which impairs cerebral perfusion pressure (CPP), results in irrepairable damage to various vital areas in the brain. Stable head position is required in long neurosurgical procedures. This is obtained with the use of clamps which fix the head rigidly. This is done usually under general anaesthesia because it produces intense painful stimuli leading to stimulation of sympathetic nervous system which in turn causes release of vasoconstrictive agents. This can impair perfusion in all organ systems. The increase in blood pressure due to sympathetic nervous system causes increase in blood flow. This causes increases in intracranial pressure which result in reduction in cerebral perfusion pressure once the auto regulatory limits are exceeded. We compared the effects of dexmedetomidine 1 µgm/kg and propofol 100 µgm/kg given as infusion over a period of 10 minutes before the induction of anaesthesia and continued till 5 minutes after pinning to attenuate the stress response while cranial pinning. In this study, we wanted to compare the effects of dexmedetomidine and propofol as infusion to attenuate the stress response while cranial pinning in patients undergoing neurosurgical procedures. METHODS This is a randomized interventional trial. Patients were divided into 2 groups of 20 each. Group 1 receiving dexmedetomidine and group 2 receiving propofol, both drugs given as infusion. Haemodynamic variables were monitored before and after cranial pinning. Data was analysed using IBM statistical package for social sciences (SPSS) statistics. The parameters recorded were analysed with the help of a statistician. RESULTS The two groups were comparable in demographic data. Incidence of tachycardia between group 1 and 2 showed that tachycardia to pinning was better controlled with propofol than dexmedetomidine (P < 0.05) which is statistically significant. There is no statistically significant difference in blood pressure values between group 1 and 2 after pinning. CONCLUSIONS From our study, we came to a conclusion that propofol was superior to dexmedetomidine in attenuating the heart rate response to cranial pinning. The effect of propofol and dexmedetomidine was comparable in attenuating the blood pressure response to cranial pinning. KEYWORDS Cranial Pinning, Dexmedetomidine, Propofol

scholarly journals Partial cortico-hippocampectomy in cats, as therapy for refractory temporal epilepsy: A descriptive cadaveric study

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0244892
Author(s):  
Jessica Zilli ◽  
Monika Kressin ◽  
Anne Schänzer ◽  
Marian Kampschulte ◽  
Martin J. Schmidt
Keyword(s):  
Temporal Lobe ◽  
Tissue Injury ◽  
Histopathological Examination ◽  
Hippocampal Sclerosis ◽  
Intraoperative Complications ◽  
Temporal Cortex ◽  
Cadaveric Study ◽  
Vascular Lesions ◽  
Temporal Epilepsy ◽  
The Brain

Cats, similar to humans, are known to be affected by hippocampal sclerosis (HS), potentially causing antiepileptic drug (AED) resistance. HS can occur as a consequence of chronic seizure activity, trauma, inflammation, or even as a primary disease. In humans, temporal lobe resection is the standardized therapy in patients with refractory temporal lobe epilepsy (TLE). The majority of TLE patients are seizure free after surgery. Therefore, the purpose of this prospective cadaveric study is to establish a surgical technique for hippocampal resection in cats as a treatment for AED resistant seizures. Ten cats of different head morphology were examined. Pre-surgical magnetic resonance imaging (MRI) and computed tomography (CT) studies of the animals’ head were carried out to complete 3D reconstruction of the head, brain, and hippocampus. The resected hippocampal specimens and the brains were histologically examined for tissue injury adjacent to the hippocampus. The feasibility of the procedure, as well as the usability of the removed specimen for histopathological examination, was assessed. Moreover, a micro-CT (mCT) examination of the brain of two additional cats was performed in order to assess temporal vasculature as a reason for possible intraoperative complications. In all cats but one, the resection of the temporal cortex and the hippocampus were successful without any evidence of traumatic or vascular lesions in the surrounding neurovascular structures. In one cat, the presence of mechanical damage (a fissure) of the thalamic surface was evident in the histopathologic examination of the brain post-resection. All hippocampal fields and the dentate gyrus were identified in the majority of the cats via histological examination. The study describes a new surgical approach (partial temporal cortico-hippocampectomy) offering a potential treatment for cats with clinical and diagnostic evidence of temporal epilepsy which do not respond adequately to the medical therapy.

scholarly journals Neuropeptides in modulation of Drosophila behavior: how to get a grip on their pleiotropic actions

2019 ◽  
Author(s):  
Dick R Nässel ◽  
Dennis Pauls ◽  
Wolf Huetteroth
Keyword(s):  
Expression Pattern ◽  
Internal State ◽  
Neurosecretory Cells ◽  
Higher Order ◽  
Specific Expression ◽  
Specific Expression Pattern ◽  
Pleiotropic Functions ◽  
Pleiotropic Actions ◽  
The Brain ◽  
Different Levels

Neuropeptides constitute a large and diverse class of signaling molecules that are produced by many types of neurons, neurosecretory cells, endocrines and other cells. Many neuropeptides display pleiotropic actions either as neuromodulators, co-transmitters or circulating hormones, while some play these roles concurrently. Here, we highlight pleiotropic functions of neuropeptides and different levels of neuropeptide signaling in the brain, from context-dependent orchestrating signaling by higher order neurons, to local executive modulation in specific circuits. Additionally, orchestrating neurons receive peptidergic signals from neurons conveying organismal internal state cues and relay these to executive circuits. We exemplify these levels of signaling with four neuropeptides, SIFamide, short neuropeptide F, allatostatin-A and leucokinin, each with a specific expression pattern and level of complexity in signaling.

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