scholarly journals Sensory and neurosecretory innervation of leech nephridia is accomplished by a single neurone containing FMRFamide

1993 ◽  
Vol 182 (1) ◽  
pp. 81-96 ◽  
Author(s):  
A. Wenning ◽  
M. A. Cahill ◽  
U. Hoeger ◽  
R. L. Calabrese

The neural control of the excretory system of the medicinal leech Hirudo medicinalis has been characterized morphologically and chemically using light and electron microscopy, immunocytochemistry and biochemistry. Immunoreactivity against RFamide-like peptides revealed elaborate neuronal aborizations of a neurone in the nephridium, around the urinary bladder sphincter and in the central nervous system. The processes arose from the nephridial nerve cell (NNC), a previously identified receptor neurone. Using a combination of reverse-phase high pressure liquid chromatography, radioimmunoassay and subsequent Edman degradation and mass spectrometry, authentic FMRFamide has been identified as the major peptide of the NNC. Sensory and neurosecretory innervation of the nephridia is thus accomplished by a single neurone, which is thought to modulate nephridial performance.

1999 ◽  
Vol 5 (S2) ◽  
pp. 498-499
Author(s):  
Francisco Capani ◽  
Maryann E. Martone ◽  
Thomas J. Deerinck ◽  
Mark H. Ellisman

Determination of the fine organization of actin networks is important for understanding different functional aspects of the central nervous system (CNS) such as plastic events. Early studies investigating the localization of actin filaments at the ultrastructural level relied on structural methods or antibodies raised against actin isoforms. More recently, many investigators have employed the actin-binding peptide phalloidin conjugated to various fluorescent molecules. By conjugating phalloidin to the fluorophore eosin, we have been able to localize f-actin at the electron microscopic level using photooxidation of diaminobenzidine (DAB) by eosin. The goal of this study is to provide a better description of the cellular and subcellular localization of actin filaments at the light and electron microscopy level based on the high binding affinity of phalloidin for actin and utilizing this novel method.Tissues were obtained from male Sprague Dawley rats that were perfused transcardially under deep anesthesia with normal rat Ringer's solution at 35°C followed by fixative. The fixative contained 4 % paraformaldehyde and different concentrations of glutaraldehyde, ranging from 0.1- 2.5%. Sections of cerebellum, striatum and hippocampus which were cut at a thickness of 50-80 μm with a Vibratome were incubated with phalloidin-eosin in a solution of 0.05% in 0.5% cold water fish gelatin/50mM glycine-PBS (“working buffer”) for 2 hrs. As a control, phalloidin-eosin was omitted for one set of tissues.


2020 ◽  
Vol 24 (1) ◽  
pp. 104-112 ◽  
Author(s):  
Krzysztof Kamil Wojtanowski ◽  
Tomasz Mroczek

Flavonoids are one of the most common secondary metabolites occurring in plants. Their activity in the Central Nervous System (CNS) including sedative, anxiolytic, anti-convulsive, anti-depressant and neuro-protective actions is well known and documented. The most popular methods for detection, identification and structural elucidation of flavonoids are these based on Nuclear Magnetic Resonance (NMR) and mass spectrometry (MS). NMR allows rapid, high throughput analysis of crude extracts and also gives stereochemical details about identified substances. However, these methods are expensive and less sensitive than MS-based techniques. Combining High Performance Liquid Chromatography (HPLC) with MS detection gives the most powerful tool for analysis of flavonoids occurring in plants. There is a lot of different approaches to use LC/MS based techniques for identification of flavonoids and this short review shows the most important.


1981 ◽  
Vol 96 (3) ◽  
pp. 394-397 ◽  
Author(s):  
Jau-Nan Lee ◽  
Markku Seppälä ◽  
Tim Chard

Abstract. High pressure liquid chromatography (HPLC) and radioimmunoassay were employed to characterize luteinizing hormone-releasing factor (LRF)-like material in the human placenta. Methanol extracts of the placenta were washed with acetic acid and chloroform, further purified on coarse octadecylsilane columns, fractionated on HPLC, and tested by radioimmunoassay. In HPLC, placental LRF had the same retention time as synthetic LRF, and such fractions gave an inhibition curve which was parallel to that of synthetic LRF in radioimmunoassav. It is concluded that human placental I.RF is similar or identical to LRF in the central nervous system.


2004 ◽  
Vol 279 (42) ◽  
pp. 43828-43837 ◽  
Author(s):  
David Vergote ◽  
Pierre-Eric Sautière ◽  
Franck Vandenbulcke ◽  
Didier Vieau ◽  
Guillaume Mitta ◽  
...  

2000 ◽  
Vol 853 (2) ◽  
pp. 245-268 ◽  
Author(s):  
Julia Serrano ◽  
L.Otto Uttenthal ◽  
Alfredo Martı́nez ◽  
A.Patricia Fernández ◽  
Javier Martı́nez de Velasco ◽  
...  

1951 ◽  
Vol 28 (4) ◽  
pp. 463-472
Author(s):  
D. B. CARLISLE

1. It is argued that the neural gland (+ciliated pit) of ascidians is homologous with the entire pituitary of vertebrates, adenohypophysis as well as neurohypophysis. 2. Ciona and Phallusia are shown to respond to an injection of chorionic gonadotrophin by the release of gametes. 3. They respond in the same way to feeding with eggs and sperm of their own species but not to those of other species. 4. This response is prevented in both cases by section of the nerves from the ganglion to the region of the gonads. 5. Destruction of the heart and removal of the blood does not prevent the response to feeding with gametes, nor to injection of gonadotrophin into the neural region; this operation does prevent the reaction if the site of injection is elsewhere. 6. Destruction of the neural gland, leaving the ganglion intact, prevents the response to feeding with gametes, but does not prevent its following an injection of chorionic gonadotrophin. 7. The hypothesis is advanced that the neural gland (+ciliated pit) is the sense organ involved in this response to feeding, and that it produces gonadotrophin and passes it to the ganglion by a non-vascular route; the ganglion then stimulates by nervous pathways the gonads to release gametes. 8. It is suggested that gonadotrophin is here fulfilling a sensory role in passing information from sense organ to the central nervous system. It may be contrasted with adrenalin which passes instructions from the central nervous system to effectors. 9. Phallusia is shown to respond with gamete release to an injection of an extract of the neural complex of Ciona.


1995 ◽  
Vol 37 (2) ◽  
pp. 137-143
Author(s):  
C.L.P. Lancellotti ◽  
C.E.P. Corbett ◽  
M.I.S. Duarte

Histopathological and ultrastructural studies of 23 patients who died with clinical diagnosis of measles were carried out. In 12 cases viral nucleocapsids were searched by electron microscopy and detected in 100% of the cases in the lungs and in 50% of the cases in the central nervous system. They were mostly intranuclear. Histopathological changes associated to neurological alterations and the detection of virion are discussed in relation to acute and delayed clinical manifestations.


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