scholarly journals The endoderm indirectly influences morphogenetic movements of the zebrafish head kidney through the posterior cardinal vein and VegfC

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Chih-Wei Chou ◽  
Hsiao-Chu Hsu ◽  
May-su You ◽  
Jamie Lin ◽  
Yi-Wen Liu
2014 ◽  
Vol 22 (2) ◽  
pp. 151-158 ◽  
Author(s):  
Padmanabha Chakrabarti ◽  
Saroj Kumar Ghosh

Abstract The present study focused on observations of the histological status of adrenocortical tissues and the correlated seasonal changes in testicular activities in Puntius sarana (Hamilton). Interrenal and chromaffin cells were located in the head kidney between the posterior cardinal vein and hemopoietic tissues. Various male germ cells were identified in the testis based on distinctive features, distribution, and staining properties. The cytoplasmic features and the architecture of the interrenal and chromaffin cells varied during different phases of the annual reproductive cycle. The cytoplasm mass was elevated throughout maturation and spawning phases; however, it was weak in the post-spawning and growth phases. The staining intensity changed in the cells showing various phases of secretory efficiency harmonized with the constitution of different testicular cells.


2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Sandeep Singh Awal ◽  
Som Subhro Biswas ◽  
Hitesh Goyal ◽  
Sampreet Kaur Awal

Abstract Background The azygos lobe is a rare anatomical variant seen in the upper lobe of right lung. It occurs during embryological development due to the failure of posterior cardinal vein to migrate supero-medially. It is often an incidental finding on imaging and is asymptomatic in majority of cases. Tuberculosis involving the azygos lobe is extremely rare. Only a few cases of tuberculosis involving the azygos lobe have been reported in literature. Case presentation We present a rare case report of tuberculosis infection involving the azygos lobe in a 57-year-old male with history of chronic cough, fever, hemoptysis, and weight loss. Conclusions The azygos lobe is usually asymptomatic, but it may be misdiagnosed as bulla, lung cyst, or abscess. In rare cases it may be associated with certain pathology such as tuberculosis, other infections, and lung cancer. Hence, it is pertinent for a radiologist to be aware of this variant when reporting chest imaging cases.


Development ◽  
2021 ◽  
Vol 148 (4) ◽  
pp. dev194993
Author(s):  
Marta Bastos de Oliveira ◽  
Katja Meier ◽  
Simone Jung ◽  
Eireen Bartels-Klein ◽  
Baptiste Coxam ◽  
...  

ABSTRACTPrevious studies have shown that Vasohibin 1 (Vash1) is stimulated by VEGFs in endothelial cells and that its overexpression interferes with angiogenesis in vivo. Recently, Vash1 was found to mediate tubulin detyrosination, a post-translational modification that is implicated in many cell functions, such as cell division. Here, we used the zebrafish embryo to investigate the cellular and subcellular mechanisms of Vash1 on endothelial microtubules during formation of the trunk vasculature. We show that microtubules within venous-derived secondary sprouts are strongly and selectively detyrosinated in comparison with other endothelial cells, and that this difference is lost upon vash1 knockdown. Vash1 depletion in zebrafish specifically affected secondary sprouting from the posterior cardinal vein, increasing endothelial cell divisions and cell number in the sprouts. We show that altering secondary sprout numbers and structure upon Vash1 depletion leads to defective lymphatic vessel formation and ectopic lymphatic progenitor specification in the zebrafish trunk.


2000 ◽  
Vol 203 (10) ◽  
pp. 1589-1597 ◽  
Author(s):  
K.N. Lapner ◽  
C.J. Montpetit ◽  
S.F. Perry

Experiments were performed on adult rainbow trout (Oncorhynchus mykiss) in vivo using chronically cannulated fish and in situ using a perfused posterior cardinal vein preparation (i) to characterise the desensitisation of chromaffin cell nicotinic receptors and (ii) to assess the ability of fish to secrete catecholamines during acute hypoxia with or without functional nicotinic receptors. Intra-arterial injection of nicotine (6.0×10(−)(7)mol kg(−)(1)) caused a rapid increase in plasma adrenaline and noradrenaline levels; the magnitude of this response was unaffected by an injection of nicotine given 60 min earlier. Evidence for nicotinic receptor desensitisation, however, was provided during continuous intravenous infusion of nicotine (1.3×10(−)(5)mol kg(−)(1)h(−)(1)) in which plasma catecholamine levels increased initially but then returned to baseline levels. To ensure that the decline in circulating catecholamine concentrations during continuous nicotine infusion was not related to changes in storage levels or altered rates of degradation/clearance, in situ posterior cardinal vein preparations were derived from fish previously experiencing 60 min of saline or nicotine infusion. Confirmation of nicotinic receptor desensitisation was provided by demonstrating that the preparations derived from nicotine-infused fish were unresponsive to nicotine (10(−)(5)mol l(−)(1)), yet remained responsive to angiotensin II (500 pmol kg(−)(1)). The in situ experiments demonstrated that desensitisation of the nicotinic receptor occurred within 5 min of receptor stimulation and that resensitisation was established 40 min later. The ability to elevate plasma catecholamine levels during acute hypoxia (40–45 mmHg; 5.3-6.0 kPa) was not impaired in fish experiencing nicotinic receptor desensitisation. Indeed, peak plasma adrenaline levels were significantly higher in the desensitised fish during hypoxia than in controls (263+/−86 versus 69+/−26 nmol l(−)(1); means +/− s.e.m., N=6-9). Thus, the results of the present study demonstrate that activation of preganglionic sympathetic cholinergic nerve fibres and the resultant stimulation of nicotinic receptors is not the sole mechanism for eliciting catecholamine secretion during hypoxia.


2000 ◽  
Vol 166 (3) ◽  
pp. 705-714 ◽  
Author(s):  
CJ Montpetit ◽  
SF Perry

The aim of the present investigation was to assess the relative contributions of cholinergic (acetylcholine) and non-cholinergic vasoactive intestinal polypeptide (VIP), and pituitary adenylate cyclase activating polypeptide (PACAP) neurotransmitters in the neuronal control of catecholamine secretion from the chromaffin tissue lining the posterior cardinal vein of the rainbow trout (Oncorhynchus mykiss). Using an in situ saline-perfused posterior cardinal vein preparation, it was demonstrated that exogenous administration of chicken VIP or human PACAP-27 caused a dose-dependent increase in adrenaline secretion; noradrenaline secretion was unaffected. Analysis of dose-response curves indicated that VIP and PACAP stimulated the secretion of adrenaline with a similar degree of potency (ED(50) for VIP=1.90x10(-11) mol/kg; ED(50) for PACAP=1.03x10(-11) mol/kg). The VIP/PACAP-elicited secretion was diminished in the presence of the VIP receptor antagonist, VIP 6-28, but was unaffected by the PACAP receptor antagonist, PACAP 6-27, or the cholinergic antagonists, hexamethonium and atropine. Thus, this is the first study to demonstrate a direct stimulatory role for VIP or PACAP in catecholamine secretion from piscine chromaffin cells. The relative contribution of cholinergic and non-cholinergic neurotransmitters in the neuronal control of catecholamine secretion from the chromaffin tissue was evaluated using an in situ nerve-stimulating technique previously validated by us in the rainbow trout. This was accomplished by comparing catecholamine secretion in the presence or absence of cholinergic and the VIP and PACAP receptor antagonists during different levels of electrical stimulation. The results demonstrated that cholinergic stimulation predominated during high frequency of electrical stimulation (20 Hz) while the non-cholinergic component prevailed at low frequency (1 Hz). Overall, the results of the present investigation demonstrate that VIP and/or PACAP may directly stimulate adrenaline secretion from trout chromaffin cells at low levels of neuronal activity. Therefore, the neuronal control of catecholamine secretion in teleosts may not be confined to cholinergic-evoked events.


2009 ◽  
Vol 296 (1) ◽  
pp. R133-R140 ◽  
Author(s):  
Steve F. Perry ◽  
Brian McNeill ◽  
Eshay Elia ◽  
Ashish Nagpal ◽  
Branka Vulesevic

We tested the hypothesis that endogenously produced hydrogen sulfide (H2S) can potentially contribute to the adrenergic stress response in rainbow trout by initiating catecholamine secretion from chromaffin cells. During acute hypoxia (water Po2 = 35 mmHg), plasma H2S levels were significantly elevated concurrently with a rise in circulating catecholamine concentrations. Tissues enriched with chromaffin cells (posterior cardinal vein and anterior kidney) produced H2S in vitro when incubated with l-cysteine. In both tissues, the production of H2S was eliminated by adding the cystathionine β-synthase inhibitor, aminooxyacetate. Cystathionine β-synthase and cystathionine γ-lyase were cloned and sequenced and the results of real-time PCR demonstrated that with the exception of white muscle, mRNA for both enzymes was broadly distributed within the tissues that were examined. Electrical field stimulation of an in situ saline-perfused posterior cardinal vein preparation caused the appearance of H2S and catecholamines in the outflowing perfusate. Perfusion with the cholinergic receptor agonist carbachol (1 × 10−6 M) or depolarizing levels of KCl (1 × 10−2 M) caused secretion of catecholamines without altering H2S output, suggesting that neuronal excitation is required for H2S release. Addition of H2S (at concentrations exceeding 5 × 10−7 M) to the perfusion fluid resulted in a marked stimulation of catecholamine secretion that was not observed when Ca2+-free perfusate was used. These data, together with the finding that H2S-induced catecholamine secretion was unaltered by the nicotinic receptor blocker hexamethonium, suggest that H2S is able to directly elicit catecholamine secretion via membrane depolarization followed by Ca2+-mediated exocytosis.


Development ◽  
1980 ◽  
Vol 55 (1) ◽  
pp. 291-306
Author(s):  
Stephen Meier

The early development of the mesoblast in the intermediate and lateral regions of the chick embryo was examined with the scanning and transmission electron microscope. It was found that primary mesenchyme here becomes condensed into epithelial structures that emerge in a metameric pattern. Viewed in developmental sequence, the intermediate mesoblast condenses into a narrowing cord of axially oriented cells which divert medially at regular intervals into the intersegmental interfaces of somitomeres and somites. These cells give rise to the vascular channels of the posterior cardinal vein as well as to tubular elements of the pronephros. Intermediate mesenchyme cells become epithelial, forming zonular junctional complexes apically and depositing patchy basal lamina over their basal surfaces. The lateral plate mesenchyme organizes similarly into somatic and splanchnic epithelial sheets that utilize the body coelom as their lumenal surface. Cells of the lateral plate extend filopodia basally that interweave with adjacent cells, fibrillar extracellular matrix, as well as with interstitial bodies. The pattern in the lateral plate is subtly ribbed as bands of mesoblast undulate along the axis. The central region of each band is raised while there are grooves created along lines of band abutment, corresponding to intersegmental clefts in the paraxial region and reflecting an underlying metameric pattern. These grooves are usually demarked medially by the protrusion of short segments of adjacent intermediate mesoblast. Most of the remaining primary mesenchyme develops into a non-metameric vascular epithelium, which forms a prominent anastamosing plexus between splanchnic mesoderm and endoderm. It is proposed that the emergence of primary mesenchyme into patterned epithelial anlage facilitates the distribution of neural crest cells introduced subsequently.


Sign in / Sign up

Export Citation Format

Share Document