Ion and Water Balance in the Ixodid Tick Dermacentor Andersoni

1973 ◽  
Vol 58 (2) ◽  
pp. 537-547
Author(s):  
W. R. KAUFMAN ◽  
J. E. PHILLIPS
Keyword(s):  
Salivary Gland ◽  
Water Balance ◽  
Fluid Secretion ◽  
Ixodid Tick ◽  
Dermacentor Andersoni ◽  
In Vitro Method ◽  
Mechanism Control ◽  
Transmitter Substance

1. An in vitro method is described for stimulating the salivary gland of Dermacentor andersoni to secrete fluid. In vitro glands require the presence of a catecholamine for salivation to occur. Natural haemolymph from salivating ticks does not trigger secretion suggesting that the tick does not produce a ‘salivation hormone’ analogous to the diuretic hormones of certain insects. 2. Piocarpine, glutamate and malate did not stimulate secretion in vitro. Isoproterenol and 5-hydroxytryptamine were relatively weak stimulants (threshold concentrations of approximately 10-5 M and greater than 10-4 M respectively). Adrenaline, noradrenaline and dopamine were highly effective stimulants, the threshold concentrations being no more than 10-5 M. Adrenaline could also elicit a copious secretion in vivo at a final haemocoele concentration of about 2 x 10-5 M. 3. We postulate that salivation occurs by means of a secretory rather than a filtration-resorption mechanism. Control of fluid secretion is probably neural rather than hormonal, the transmitter substance being a catecholaminergic substance.

Ion and Water Balance in the Ixodid Tick Dermacentor Andersoni

1973 ◽  
Vol 58 (2) ◽  
pp. 549-564
Author(s):  
W. R. KAUFMAN ◽  
J. E. PHILLIPS
Keyword(s):  
Salivary Gland ◽  
Fluid Secretion ◽  
Ixodid Tick ◽  
Artificial Medium ◽  
Salivary Duct ◽  
Bathing Medium ◽  
Dermacentor Andersoni ◽  
Cl Secretion ◽  
Wide Range

1. The salivary gland of the ixodid tick, Dermacentor andersoni, can be induced to secrete fluid for at least 6 h when bathed in an artificial medium in vitro. 2. Fluid secretion appears to be a consequence of active Cl secretion since (a) it is inhibited by 95% when nitrate and by 100% when acetate replaces Cl in the bathing medium; however, bromide can support secretion as well as Cl, (b) the rates of fluid and Cl secretion are linearly related to the concentration of Cl in the medium; and (c) the S/H ratio for Cl is greater than unity at all concentrations despite a transacinar P.D. of 35 mV (lumen negative). 3. Although (in the presence of Na) a low concentration of K in the bathing medium stimulates the rate of fluid secretion fivefold, higher concentrations of K inhibit fluid secretion. The latter is largely due to a direct effect of K ion and not simply to increased osmotic pressure or reduced Na concentration. Fluid secretion is completely in hibited by 10-6 M ouabain. On the basis of these observations we propose that fluid secretion may be dependent on a Na-K activated ‘pump ATPase’, which is somehow involved in cation secretion. The S/H ratios of Na and K are greater than unity at all medium concentrations. 4. The saliva secreted in vitro is slightly hypo-osmotic to the bathing medium over a wide range of medium concentration (300-920 mOsm/l). We postulate that the primary saliva is iso- or hyper-osmotic to the bathing medium; the final elaborated saliva is probably rendered hypo-osmotic by a process of solute reabsorption somewhere between the acini and the orifice of the main salivary duct.

The influence of various factors on fluid secretion by in vitro salivary glands of ixodid Ticks

1976 ◽  
Vol 64 (3) ◽  
pp. 727-742
Author(s):  
W. Kaufman
Keyword(s):  
Salivary Gland ◽  
Salivary Glands ◽  
Culture Medium ◽  
Dry Weight ◽  
Fluid Secretion ◽  
Ixodid Tick ◽  
Ixodid Ticks ◽  
Mammalian Tissue ◽  
Stimulating Factor

1. Salivary glands of the female ixodid tick, Dermacentor andersoni, secrete fluid in vitro when bathed in a slightly modified version of the mammalian tissue culture medium ‘TC 199′. 2. Rate of salivation in vitro increases with progression of feeding, but there is no comparable increase in dry weight of the salivary glands during the early phase of engorgement. Engorged ticks secreted at only 25% the rate of 90–250 mg ticks, indicating that salivary gland degeneration has already begun in the very early post-engorgement stage. 3. A salivary gland stimulating factor can be detected in the nervous system but not in other tissues. 4. Male salivary glands secrete at only 1/20th the rate of female glands. Thus males probably do not use their salivary glands as osmoregulatory organs. 5. From the uniform lack of response to ACh and uniform response to DA in 7 ixodid tick species, it is suggested that the control of salivation is similar throughout the ixodid family.

A proposed site of fluid secretion in the salivary gland of the ixodid tick Dermacentor andersoni

Parasitology ◽  
1973 ◽  
Vol 67 (2) ◽  
pp. 205-217 ◽  
Author(s):  
Joan Meredith ◽  
William R. Kaufman
Keyword(s):  
Salivary Gland ◽  
Granule Cells ◽  
Fluid Secretion ◽  
Ixodid Tick ◽  
Dermacentor Andersoni ◽  
Group Iii ◽  
Group I ◽  
Main Cell Type ◽  
Protein Rich ◽  
Vacuolar Cell

The histology and ultrastructure of the salivary gland in Dermacentor andersoni are presented with particular emphasis on those aspects relating to fluid secretion. We suggest that the group III acinus contributes most of the fluid portion of the saliva (i.e. water and small molecules) and that the main cell-type involved is what we name the ‘water-cell’. The granule-cells possibly secrete the cement by which the tick secures its mouthparts to the host, and the ‘vacuolar cell’ possibly produces a protein-rich secretion. The function of the group I acinus remains obscure.

A in Vivo Assay for Standardizing Heparin Preparations

1979 ◽  
Vol 41 (03) ◽  
pp. 576-582
Author(s):  
A R Pomeroy
Keyword(s):  
In Vitro Assays ◽  
British Pharmacopoeia ◽  
In Vitro Method ◽  
Standard Preparation ◽  
Reliable Estimation ◽  
Assay Procedure ◽  
Accuracy And Precision ◽  
Heparin Preparation

SummaryThe limitations of currently used in vitro assays of heparin have demonstrated the need for an in vivo method suitable for routine use.The in vivo method which is described in this paper uses, for each heparin preparation, four groups of five mice which are injected intravenously with heparin according to a “2 and 2 dose assay” procedure. The method is relatively rapid, requiring 3 to 4 hours to test five heparin preparations against a standard preparation of heparin. Levels of accuracy and precision acceptable for the requirements of the British Pharmacopoeia are obtained by combining the results of 3 to 4 assays of a heparin preparation.The similarity of results obtained the in vivo method and the in vitro method of the British Pharmacopoeia for heparin preparations of lung and mucosal origin validates this in vivo method and, conversely, demonstrates that the in vitro method of the British Pharmacopoeia gives a reliable estimation of the in vivo activity of heparin.

scholarly journals Design of PSMA ligands with modifications at the inhibitor part: an approach to reduce the salivary gland uptake of radiolabeled PSMA inhibitors?

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Veronika Barbara Felber ◽  
Manuel Amando Valentin ◽  
Hans-Jürgen Wester
Keyword(s):  
Salivary Gland ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis ◽  
In Vivo Studies ◽  
Tumor Xenograft ◽  
Tumor Uptake ◽  
Lncap Cells ◽  
High Affinity

Abstract Aim To investigate whether modifications of prostate-specific membrane antigen (PSMA)-targeted radiolabeled urea-based inhibitors could reduce salivary gland uptake and thus improve tumor-to-salivary gland ratios, several analogs of a high affinity PSMA ligand were synthesized and evaluated in in vitro and in vivo studies. Methods Binding motifs were synthesized ‘on-resin’ or, when not practicable, in solution. Peptide chain elongations were performed according to optimized standard protocols via solid-phase peptide synthesis. In vitro experiments were performed using PSMA+ LNCaP cells. In vivo studies as well as μSPECT/CT scans were conducted with male LNCaP tumor xenograft-bearing CB17-SCID mice. Results PSMA ligands with A) modifications within the central Zn2+-binding unit, B) proinhibitor motifs and C) substituents & bioisosteres of the P1′-γ-carboxylic acid were synthesized and evaluated. Modifications within the central Zn2+-binding unit of PSMA-10 (Glu-urea-Glu) provided three compounds. Thereof, only natLu-carbamate I (natLu-3) exhibited high affinity (IC50 = 7.1 ± 0.7 nM), but low tumor uptake (5.31 ± 0.94% ID/g, 1 h p.i. and 1.20 ± 0.55% ID/g, 24 h p.i.). All proinhibitor motif-based ligands (three in total) exhibited low binding affinities (> 1 μM), no notable internalization and very low tumor uptake (< 0.50% ID/g). In addition, four compounds with P1′-ɣ-carboxylate substituents were developed and evaluated. Thereof, only tetrazole derivative natLu-11 revealed high affinity (IC50 = 16.4 ± 3.8 nM), but also this inhibitor showed low tumor uptake (3.40 ± 0.63% ID/g, 1 h p.i. and 0.68 ± 0.16% ID/g, 24 h p.i.). Salivary gland uptake in mice remained at an equally low level for all compounds (between 0.02 ± 0.00% ID/g and 0.09 ± 0.03% ID/g), wherefore apparent tumor-to-submandibular gland and tumor-to-parotid gland ratios for the modified peptides were distinctly lower (factor 8–45) than for [177Lu]Lu-PSMA-10 at 24 h p.i. Conclusions The investigated compounds could not compete with the in vivo characteristics of the EuE-based PSMA inhibitor [177Lu]Lu-PSMA-10. Although two derivatives (3 and 11) were found to exhibit high affinities towards LNCaP cells, tumor uptake at 24 h p.i. was considerably low, while uptake in salivary glands remained unaffected. Optimization of the established animal model should be envisaged to enable a clear identification of PSMA-targeting radioligands with improved tumor-to-salivary gland ratios in future studies.

scholarly journals Rotavirus Infection Is Not Associated with Small Intestinal Fluid Secretion in the Adult Mouse

2006 ◽  
Vol 80 (22) ◽  
pp. 11355-11361 ◽  
Author(s):  
Shirin Kordasti ◽  
Claudia Istrate ◽  
Mahanez Banasaz ◽  
Martin Rottenberg ◽  
Henrik Sjövall ◽  
...  
Keyword(s):  
Fluid Secretion ◽  
Chloride Secretion ◽  
Potential Difference ◽  
Pathophysiological Mechanism ◽  
Rotavirus Infection ◽  
In Vivo Experiments ◽  
Adult Mice ◽  
Small Intestines

ABSTRACT In contrast to humans, adult but not infant small animals are resistant to rotavirus diarrhea. The pathophysiological mechanism behind this age-restricted diarrhea is currently unresolved, and this question was investigated by studying the secretory state of the small intestines of adult mice infected with rotavirus. Immunohistochemistry and histological examinations revealed that rotavirus (strain EDIM) infects all parts of the small intestines of adult mice, with significant numbers of infected cells in the ilea at 2 and 4 days postinfection. Furthermore, quantitative PCR revealed that 100-fold more viral RNA was produced in the ilea than in the jejuna or duodena of adult mice. In vitro perfusion experiments of the small intestine did not reveal any significant changes in net fluid secretion among mice infected for 3 days or 4 days or in those that were noninfected (37 ± 9 μl · h−1 · cm−1, 22 ± 13 μl · h−1 · cm−1, and 33 ± 6 μl · h−1 · cm−1, respectively) or in transmucosal potential difference (4.0 ± 0.3 mV versus 3.9 ± 0.4 mV), a marker for active chloride secretion, between control and rotavirus-infected mice. In vivo experiments also did not show any differences in potential difference between uninfected and infected small intestines. Furthermore, no significant differences in weight between infected and uninfected small intestines were found, nor were any differences in fecal output observed between infected and control mice. Altogether, these data suggest that rotavirus infection is not sufficient to stimulate chloride and water secretion from the small intestines of adult mice.

Influence of pilocarpine on transport by salivary gland slices

1963 ◽  
Vol 205 (5) ◽  
pp. 1058-1062 ◽  
Author(s):  
L. H. Schneyer ◽  
C. A. Schneyer
Keyword(s):  
Salivary Gland ◽  
Submaxillary Gland ◽  
Nitrogen Atmosphere ◽  
Total Water ◽  
Early Effect ◽  
Apparent Loss ◽  
Inulin Space ◽  
Total Tissue

Effects of pilocarpine on net movements of water and electrolytes in gland cells were investigated in vitro, using slices from submaxillary gland of rat. Slices were depleted of K, and loaded with Na, Cl, and water, by incubation in Krebs-Ringer phosphate with nitrogen atmosphere. After this, the slices were transferred to Krebs-Ringer phosphate with oxygen atmosphere. During this period with O2, pilocarpine caused apparent loss of water from cells, since tissue total water decreased and inulin space remained almost unchanged. Without pilocarpine during this time, water in cells increased. Electrolyte movements were also affected by pilocarpine. Specifically, there occurred reduction in net accumulation of K in total tissue and cells. Reduction in net extrusion of Na was suggested. Since, in vivo, an early effect of stimulation involves depletion of gland K, it appears that the current observations have relevance to normal secretion to the extent, at least, that in both circumstances stimulating agents reduce the ability of the cells to maintain stores of K.

scholarly journals Inhibition of Alk signaling promotes the induction of human salivary-gland-derived organoids

2020 ◽  
Vol 13 (9) ◽  
pp. dmm045054 ◽  
Author(s):  
Shohei Yoshimoto ◽  
Junko Yoshizumi ◽  
Hiromasa Anzai ◽  
Koichiro Morishita ◽  
Kazuhiko Okamura ◽  
...  
Keyword(s):  
Salivary Gland ◽  
Fungal Infections ◽  
Disease Model ◽  
Good Health ◽  
Functional Changes ◽  
Human Salivary Gland ◽  
Saliva Secretion ◽  
Tnf Α

ABSTRACTHyposalivation and xerostomia are the cause of several morbidities, such as dental caries, painful mucositis, oral fungal infections, sialadenitis and dysphagia. For these reasons, preservation of normal saliva secretion is critical for the maintenance of functionally normal oral homeostasis and for keeping good health. Several strategies for restoring salivary gland function have been reported, from different points of view, based on the use of salivary-gland-derived epithelial stem/progenitor cells and tissue engineering approaches to induce organoids that mimic in vivo salivary glands. In this study, we clarified that inhibition of activin receptor-like kinase (Alk) signaling was essential for the induction of human salivary-gland-derived organoids, and demonstrated the usefulness of such organoids as an inflammatory disease model. In inflammatory conditions like sialadenitis, in general, pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α, also known as TNF) are upregulated, but their function is still unclear. In our established human salivary-gland-derived organoid culture system, we successfully induced organoid swelling by stimulation with carbachol, a non-selective cholinergic agonist, and forskolin, an activator of cystic fibrosis transmembrane conductance regulator (CFTR). Furthermore, we found that this organoid swelling was inhibited by TNF-α. From these results, we could clarify the inhibitory function of TNF-α on saliva secretion in vitro. Thus, our established human salivary-gland-derived organoids would be useful for in vitro analyses of the morphological and functional changes involved in salivary gland dysfunctions in several research fields, such as pathobiology, inflammation and regenerative medicine.This article has an associated First Person interview with the first author of the paper.

Hypno-desensitization therapy of vaginismus: Part I. “in vitro” method. Part II. “in vivo” method

1973 ◽  
Vol 21 (3) ◽  
pp. 144-156 ◽  
Author(s):  
K. Fuchs ◽  
Z. Hoch ◽  
E. Paldi ◽  
H. Abramovici ◽  
J. M. Brandes ◽  
...  
Keyword(s):  
In Vitro Method ◽  
Desensitization Therapy

scholarly journals Functional analysis of the biochemical activity of mammalian phosphatidylinositol 5 phosphate 4-kinase enzymes

2019 ◽  
Vol 39 (2) ◽  
Author(s):  
Swarna Mathre ◽  
K. Balasankara Reddy ◽  
Visvanathan Ramya ◽  
Harini Krishnan ◽  
Avishek Ghosh ◽  
...  
Keyword(s):  
Salivary Gland ◽  
Cell Size ◽  
Kinase Activity ◽  
Gland Cell ◽  
Specific Activity ◽  
Salivary Gland Cell ◽  
Drosophila Genome ◽  
Biochemical Activity

Abstract Phosphatidylinositol 5 phosphate 4-kinase (PIP4K) are enzymes that catalyse the phosphorylation of phosphatidylinositol 5-phosphate (PI5P) to generate PI(4,5)P2. Mammalian genomes contain three genes, PIP4K2Α, 2B and 2C and murine knockouts for these suggested important physiological roles in vivo. The proteins encoded by PIP4K2A, 2B and 2C show widely varying specific activities in vitro; PIP4K2A is highly active and PIP4K2C 2000-times less active, and the relationship between this biochemical activity and in vivo function is unknown. By contrast, the Drosophila genome encodes a single PIP4K (dPIP4K) that shows high specific activity in vitro and loss of this enzyme results in reduced salivary gland cell size in vivo. We find that the kinase activity of dPIP4K is essential for normal salivary gland cell size in vivo. Despite their highly divergent specific activity, we find that all three mammalian PIP4K isoforms are able to enhance salivary gland cell size in the Drosophila PIP4K null mutant implying a lack of correlation between in vitro activity measurements and in vivo function. Further, the kinase activity of PIP4K2C, reported to be almost inactive in vitro, is required for in vivo function. Our findings suggest the existence of unidentified factors that regulate PIP4K enzyme activity in vivo.

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