scholarly journals LOCUST MEDIAL NEUROSECRETORY CELLS IN VITRO: MORPHOLOGY, ELECTROPHYSIOLOGICAL PROPERTIES AND EFFECTS OF TEMPERATURE

1993 ◽  
Vol 183 (1) ◽  
pp. 323-339
Author(s):  
W. Rossler ◽  
U. Bickmeyer

The medial neurosecretory cells of the pars intercerebralis in the protocerebrum of larval and adult locusts (Locusta migratoria) were cultured in a chemically defined serum-free culture medium. The morphology of the cells was investigated by light microscopy and the electrophysiological properties were studied using the patch-clamp technique in the whole-cell configuration. The dissociated neurosecretory cells grew new processes under these conditions and were maintained in culture for up to 2 months. The percentage of cells showing outgrowth was significantly higher in third-instar larvae than in instars 4 and 5 and adults. A primary axonal stump promoted a unipolar cell morphology; in other cases, most neurosecretory cells became multipolar. The presence of glial cells in undissociated groups of neurosecretory cells improved outgrowth and the formation of neurite bundles. A considerable number of the recorded cells showed spiking activity in response to depolarization. The influences of temperature on spike frequency, duration and amplitude as well as on membrane potential and ionic currents were investigated. The results suggest that temperature may directly affect the function of neurosecretory cells.

1994 ◽  
Vol 197 (1) ◽  
pp. 393-398
Author(s):  
U Bickmeyer ◽  
W RÖssler ◽  
H Wiegand

The medial neurosecretory cells (MNSCs) of the pars intercerebralis in the brain of insects release various hormonal factors that control essential physiological and developmental functions such as moulting, reproduction and metabolism (Wigglesworth, 1940; Girardie, 1966; Goldsworthy, 1969), and these cells are therefore of considerable biological significance. A culture system for locust embryonic pars intercerebralis neurosecretory cells has recently been developed (Vanhems et al. 1993), and Rossler and Bickmeyer (1993) have established an in vitro system for growing larval and adult medial neurosecretory cells. Calcium plays an important role in neural physiology: neurosecretion depends on calcium influx into the cells and calcium currents carry the rising phase of action potentials in different types of insect neurones (Orchard, 1976; Pitman, 1979); calcium also mediates other ionic currents (Thomas, 1984). It is therefore of considerable interest to characterize the types of calcium channel currents found in locust neurosecretory neurones.


Blood ◽  
1974 ◽  
Vol 44 (1) ◽  
pp. 77-85 ◽  
Author(s):  
Allan J. Erslev

Abstract Normal rabbits exposed to 0.4 atmospheric pressure for 3 hr will generate about 40-60 U of erythropoietin during a subsequent 3-hr period. If the kidneys were removed from 3-hr hypoxic animals, washed carefully, and perfused for 3 hr by recirculation with a serum-tissue culture mixture, each kidney generated about 14 U of erythropoietin in vitro. Perfusion of normal kidneys did not result in the production of erythropoietin, and only small amounts were generated if the perfusate contained Puromycin. Three-hour hypoxic kidneys perfused for 3 hr with a serum-free tissue culture medium were found to generate about 8 U of erythropoietin per kidney and similar kidneys perfused with saline about 1 U. These results indicate that erythropoietin is synthesized by kidney tissue and not produced by enzymatic activation of a plasma substrate.


2021 ◽  
Vol 8 ◽  
Author(s):  
Yukina Kuwahara ◽  
Karin Yoshizaki ◽  
Hidetaka Nishida ◽  
Hiroaki Kamishina ◽  
Sadatoshi Maeda ◽  
...  

Mesenchymal stem/stromal cells (MSCs) have been used as cell sources for treating dogs with naturally-occurring diseases. Extracellular vesicles (EVs) derived from MSCs are now recognized as pivotal to modulating the immune response and supporting tissue repair. Manufacture of MSC-EVs for clinical application mandates removal of the xeno-proteins, including fetal bovine serum. The objective of this study was to examine whether canine MSCs survived and secreted EVs in serum-free medium (SFM) conditions and to assess the immunomodulatory effect of EVs in vitro. Canine MSCs were found to survive and secrete EVs under SFM conditions. The surface markers of MSCs in the SFM were similar to MSCs in complete culture medium. Canine MSC-EVs had a diameter of ~300 nm and were positive for EV markers. MSC-derived EVs from the serum-free condition reduced the levels of IL-1β by BV-2 cells in response to LPS stimulation. These results warrant further studies of the use of SFM for producing EVs derived from canine MSCs.


2005 ◽  
Vol 17 (2) ◽  
pp. 217 ◽  
Author(s):  
C. Daniaux ◽  
B. Verhaeghe ◽  
I. Donnay

Serum in embryo culture medium may be a potential cause of abnormal accumulation of lipid droplets, which is correlated to a higher sensitivity to cryopreservation. Moreover, serum may introduce pathogens. With the aim of developing a serum-free culture medium, we first (Experiment 1) investigated the effect of adding ITS (5 μg/mL insulin, 5 μg/mL transferrin, 5 ng/mL selenium) as a serum substitute in SOF medium on embryos cultured in large groups (20 embryos per culture drop of 20 μL) and we then (Experiment 2) analyzed the effect of adding BSA. In this second experiment, our serum-free culture media were also tested on embryos cultured in small numbers (5 embryos per drop of 20 μL) in order to mimic ovum pickup (OPU) conditions. Embryos were obtained from slaughterhouse oocytes, matured in vitro for 24 h in a serum-free enriched 199 medium (Donnay et al. 2004 Reprod. Fertil. Dev. 16, 274) containing ITS, and fertilized for 18 h. In experiment 1, embryos were cultured in SOF (Holm et al. 1999 Theriogenology 52, 683–700) supplemented with 0.1 mg/mL polyvinylpyrrolidane (PVP) without (SOF) or with ITS (SOF-ITS), or with 5% FCS (SOF-FCS). Cavitation occurred earlier in presence of serum (Table). Adding ITS to SOF increased blastocyst rates at Day 7 and Day 8 post-insemination (p.i.) and also the hatching rate. In experiment 2, embryos were cultured in SOF-FCS, SOF-ITS, or SOF-ITS supplemented with 4 mg/mL fatty acid free BSA (SOF-ITS-BSA). Within each condition, no differences were observed for blastocyst and hatching rates between embryos cultured in large or in small groups. Adding BSA to SOF-ITS increased blastocyst rate at Day 6 p.i. and also the hatching rate. At Days 7 and 8 p.i., blastocyst rates were higher in SOF-FCS than in SOF-ITS and tended to be higher than in SOF-ITS-BSA, especially for embryos cultured in small groups. Cell numbers of the resulting embryos were unaffected. These results indicate that: (1) ITS as supplement to SOF medium promotes embryo development in vitro. (2) BSA as protein supplement to SOF-ITS medium accelerates blastulation and improves hatching rate. (3) SOF-ITS and SOF-ITS-BSA are two serum-free culture media that can sustain development of embryos, also when cultured in small number, even though SOF-FCS tended to afford better rates of development. Further studies will include evaluation of other quality parameters including resistance to cryopreservation. This work was supported by the Ministery of Agriculture of the Region wallonne de Belgique.


2006 ◽  
Vol 18 (2) ◽  
pp. 188
Author(s):  
F. George ◽  
C. Daniaux ◽  
G. Genicot ◽  
F. Focant ◽  
B. Verhaeghe ◽  
...  

In vitro-produced (IVP) bovine blastocysts are known to be more sensitive to cryopreservation than their in vivo counterparts. Removing serum from the culture medium decreases sanitary risk and could improve embryo resistance to cryopreservation by preventing the accumulation of intracellular lipids. Our objectives were to evaluate the lipid content, resistance to cryopreservation, and sex ratio of IVP embryos cultured in a serum-free system. Oocytes from slaughterhouse ovaries were matured in a serum-free enriched medium (Donnay et al. 2004 Reprod. Fertil. Dev. 16, 274) and cultured in 5% O2 in modified SOF supplemented with 5% FCS (FCS) or with insulin-transferrin-selenium (ITS) and 0.1 mg/mL polyvinylpyrrolidone (PVP) (ITS-PVP) or 4 mg/mL BSA (ITS-BSA) (Daniaux et al. 2005 Reprod. Fertil. Dev. 17, 217). Day 5 morulae were stained with the fluorescent dye Nile Red in order to evaluate their lipid content (Genicot et al. 2005 Theriogenology 63, 1181). Day 7 blastocysts (diameter ≥160 µm) were selected, classified according to their size, and frozen in HEPES-SOF containing 1.5 M ethylene glycol, 0.1 M sucrose, and 1.8 mg/mL wheat peptones (George et al. 2002 Reproduction 29, 51). The lipid content was significantly lower in morulae cultured in ITS-BSA compared with the two other media (320 ± 10 arbitrary fluorescence units vs. 383 ± 12 in FCS and 406 ± 10 in ITS-PVP; n = 271; ANOVA2: P < 0.01). After cryopreservation, a higher total hatching rate was found 24 h post-thawing in blastocysts cultured in ITS-BSA and for both serum-free conditions at 48 h (Table 1). In particular, embryos ≤180 µm cultured in FCS were less resistant to cryopreservation than embryos of the same size produced without serum. Expanded blastocysts cultured in ITS-BSA were sexed by PCR (Grisart et al. 1995 Theriogenology 43, 1097) and a higher proportion of male embryos was found (62.7%; n = 51). In conclusion, a complete serum-free system was set up from oocyte maturation to embryo cryopreservation that gave high quality embryos resistant to cryo-preservation. Embryos produced in ITS-BSA presented a lower lipid content, but a shift of the expanded blastocyst sex ratio toward males was observed. Table 1. Hatching rates post-thawing as a function of the blastocyst size and the culture medium


2014 ◽  
Vol 963 ◽  
pp. 40-46 ◽  
Author(s):  
Carole Mélin ◽  
Aurélie Perraud ◽  
Christophe Bounaix Morand du Puch ◽  
Elodie Loum ◽  
Stéphanie Giraud ◽  
...  

1995 ◽  
Vol 43 (1) ◽  
pp. 328 ◽  
Author(s):  
T.K. Suhl ◽  
K.L. White ◽  
T.D. Bunch ◽  
R. Spendlove ◽  
R. Wilkinson

2005 ◽  
Vol 17 (9) ◽  
pp. 102
Author(s):  
S. Zhang ◽  
A. J. French ◽  
R. T. Tecirlioglu

Culture medium supplemented with sera is commonly used for the in vitro production (IVP) of livestock embryos. However, serum induced complications including batch variation, the potential risk of virus and mycoplasma contamination and the implication in the large offspring syndrome in domestic animals impels the development of a serum-free culture system. In this study, we investigated whether replacement of fetal bovine serum (FBS) with bovine serum albumin (BSA) in three maturation media, tissue culture medium-199 (TCM-199), a modified synthetic oviduct fluid (mSOF) routinely used in our laboratories and a commercially available SOF-VC (Vitro Cleave, Cook Australia). Harvested oocytes were matured, parthenogenetically activated and in vitro cultured (Day 7) to measure maturation efficiency, embryo development and quality with the aim of developing a simplified and defined culture medium for the in vitro production of bovine embryos. Abattoir derived cumulus oocyte complexes were matured in TCM-199, mSOF and SOF-VC media supplemented with LH and beta-estradiol in the presence of 15% FBS or 0.08% BSA at 39ºC in 5% CO2 in air. Polar body extrusion was assessed twenty-two hour post maturation and selected MII occytes were activated using calcium ionophore/6-dimethylaminopurine and cultured for seven days in SOF medium supplemented with 0.8% BSA. On day seven, blastocyst development was assessed and randomly selected blastocysts were stained to determine inner cell mass (ICM), trophectoderm (TE) and total cell numbers (TCN). Supplementation with either BSA or FCS did not significantly affect the maturation efficiency, blastocyst rates or differential cell numbers within each maturation media tested. However, maturation efficiency and blastocyst rates were significantly lower (P < 0.01) when oocytes were matured in either mSOF or SOF-VC regardless of FBS or BSA supplementation. From this study, we conclude that BSA effectively replaces FCS and TCM-199 is superior to SOF (mSOF or SOF-VC) in terms of oocyte maturation regardless of protein source. Once matured SOF and TCM-199 parthenogenetically blastocysts were equivalent in terms of embryo development and quality.


2011 ◽  
Vol 108 ◽  
pp. 116-120
Author(s):  
Jin Sheng Sun ◽  
Li Ping Wang ◽  
Xu Yun Geng

The Whole-cell patch clamp technique was used to study the properties of voltage dependent ion channel expressed by the cultured types A、B、C neurosecretory cells dissociated from medulla terminalis X-organ (MTXO) of Chinese mitten crab Eriocheir sinensis 24-48 hours after plating. Under voltage clamp conditions, significantly inward currents were recorded from all three kinds of neurons, followed by large outward currents. When outward currents were suppressed with use of 3mmol/L 4-aminopyridine (4-AP) and 30mmol/L tetraethylammonium (TEA), a tetrodotoxin-sensitive Na+ current (INa) and a slow (time to peak current 6~8mS at +10mV), Cd2+-sensitive Ca2+ current (ICa) were resolved. INa was activated at potential-40mV and was maximal at-10mV. In TTX, ICa was activated at potential-30mV, was maximal at 10~20mV. In the presence of 1mol/L TTX and 0.5mmol/L Cd2+, a 4-AP-sensitive transient current and a slower-rising, TEA-sensitive current were recorded from a holding potential of-50mV. On the basis of electric feature and pharmacology, transient current was identified as IA, and late, slower-rising current as IK. IA and IK showed the same activation threshold of-30mV. In conclusion, no differences were observed on the properties and kinetics of ionic current among the three kinds of neurons. By comparison with those described in crab Cardisoma carnifex and crayfish Procambarus clarkia, there existed diversity of excitability in X-organ peptidergic neurons from different crustaceans.


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