Action of rat submaxillary gland extracts on neural tube growth in organ culture

For a long time embryologists have been interested in mechanisms which control growth of the neural tube. The results of experiments made on amphibian and chick embryos suggested that the differential growth of different portions of the neural tube is dependent both on genetic factors and on the degree of development of peripheral tissues (see Weiss, 1955). The mechanism of this peripheral action has not yet been elucidated. It has been attributed to diffusible substances from peripheral tissues acting on the growing neural tube. However, according to Hamburger (1958), the junction between neurons and peripheral tissue is necessary for this growth effect to occur. Studies on a neural growth factor found in mouse sarcoma 180 tissue, snake venom and mouse and rat submaxillary glands (Levi Montalcini, 1959) has renewed interest in this problem. However, this factor acts only on sympathetic and spinal ganglia and not on neural tube derivatives.

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Sympathetic input modulates, but does not determine, phase of peripheral circadian oscillators

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00498.2007 ◽

2008 ◽

Vol 295 (1) ◽

pp. R355-R360 ◽

Cited By ~ 78

Author(s):

Nina Vujović ◽

Alec J. Davidson ◽

Michael Menaker

Keyword(s):

Clock Genes ◽

Sympathetic Innervation ◽

Submaxillary Gland ◽

Light Cycle ◽

Restricted Feeding ◽

Peripheral Tissues ◽

Submaxillary Glands ◽

Peripheral Oscillators ◽

Circadian Oscillators ◽

Environmental Light

The circadian clock in the suprachiasmatic nucleus (SCN) maintains phase synchrony among circadian oscillators throughout the organism. Environmental light signals entrain the SCN, but timed, limited meal access acts as an overriding time cue for several peripheral tissues. We present data from a peripheral oscillator, the submaxillary salivary gland, in which temporal restriction of meals fails to entrain gene expression. In day-fed rats, submaxillary gland rhythms in expression of the clock gene Period1 ( Per1) stay entrained to the light cycle (peaking at night) or become arrhythmic. This result suggests that feeding cues compete weakly with light cycle cues to set the phase of clock genes in this tissue. Since the submaxillary glands receive sympathetic innervation originating in the SCN, which relays light cycle cues to other oscillators, we attempted to assess the role of this neural input in phase control of submaxillary Per1 expression. We sympathetically denervated the submaxillary glands before subjecting rats to daytime-restricted feeding. After denervation, Per1 rhythms in all submaxillary glands shifted phase 180° and entrained to daytime feeding. These results support the hypothesis that peripheral oscillators may receive multiple signals contributing to their phase of entrainment. Sympathetic efferents from the SCN can relay light cycle information, while other external cues may reach tissues through other efferents or nonneural pathways. In an abnormal, disruptive regimen such as daytime-restricted feeding, these different signals compete. Arrhythmicity may result if one signal is not clearly dominant. Elimination of the dominant signal (e.g., surgical sympathectomy) may allow a secondary signal to control phase.

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Differential growth effect of regenerating (reg) protein on a rat ß-cell line

Gastroenterology ◽

10.1016/s0016-5085(01)81684-x ◽

2001 ◽

Vol 120 (5) ◽

pp. A338-A339

Author(s):

Z FAN ◽

H WU ◽

S PATEL ◽

M ZENILMAN

Keyword(s):

Cell Line ◽

Growth Effect ◽

Differential Growth

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FURTHER STUDIES CONCERNING THE FILTRABLE VIRUS PRESENT IN THE SUBMAXILLARY GLANDS OF GUINEA PIGS

Journal of Experimental Medicine ◽

10.1084/jem.46.6.935 ◽

1927 ◽

Vol 46 (6) ◽

pp. 935-956 ◽

Cited By ~ 17

Author(s):

Ann G. Kuttner

Keyword(s):

Guinea Pig ◽

Guinea Pigs ◽

Active Material ◽

Active Agent ◽

Submaxillary Gland ◽

Intracerebral Inoculation ◽

Submaxillary Glands ◽

Direct Inoculation ◽

In Series ◽

Subcutaneous Inoculation

1. It has been shown that the guinea pig virus localizes in the submaxillary glands of young guinea pigs following subcutaneous, intraperitoneal, or intravenous injection of active material, and that the specific lesion is demonstrable in the glands in 12 to 15 days. When an active infection of the gland has been produced in this way, the guinea pigs are refractory to intracerebral inoculation of the virus. 2. No lesion develops in the submaxillary glands of young guinea pigs injected subcutaneously with guinea pig virus which has been inactivated by heat. Young guinea pigs which have received injections of heat-killed virus do not become refractory to intracerebral inoculation of the virus. 3. When young guinea pigs from which both submaxillary glands have been removed are injected subcutaneously with active virus, the virus localizes in the parotid gland, and the animals become refractory to intracerebral inoculation. 4. It has been impossible to demonstrate virucidal properties in the sera of adult guinea pigs which have become spontaneously infected with the virus, or in the sera of young guinea pigs which have been artificially rendered refractory to intracerebral inoculation. 5. It has been possible to transmit the virus from guinea pig to guinea pig continuously in series through seven animals by direct inoculation from submaxillary gland to submaxillary gland. 6. The fact that the virus regularly localizes in the submaxillary glands following subcutaneous inoculation has been utilized in passing the virus from guinea pig to guinea pig. 2 weeks after the subcutaneous inoculation of the virus into young guinea pigs, the active agent was present in the submaxillary glands. Emulsions of the submaxillary glands of these animals were then used for the subcutaneous injection of another group of young guinea pigs. In this way the virus was transmitted continuously from skin to submaxillary gland through a series of seven animals.

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QUANTITATIVE STUDIES OF PROSTATIC SECRETION

Journal of Experimental Medicine ◽

10.1084/jem.97.5.663 ◽

1953 ◽

Vol 97 (5) ◽

pp. 663-680 ◽

Cited By ~ 29

Author(s):

Charles Huggins ◽

John Lambert Sommer

Keyword(s):

Structural Changes ◽

Testosterone Propionate ◽

Estrogenic Activity ◽

Submaxillary Gland ◽

Critical Factors ◽

Simple Arithmetic ◽

Estrogenic Compounds ◽

Submaxillary Glands ◽

Quantitative Studies ◽

Prostatic Epithelium

The prostate of the dog was relocated permanently in the perineum where its size could be measured and correlated with the output of prostatic secretion during many months. The secretion of a submaxillary gland obtained through a fistula was utilized as an internal biologic standard of the effects of pilocarpine, the secretory stimulus employed, because the amount and route of administration of the alkaloid are critical factors in inducing secretion. Prostatic secretion was found to be profoundly affected by androgenic and estrogenic compounds, in contrast to salivation. The curves of the secretory response of the prostate and submaxillary glands to pilocarpine proved to be similar and a mathematical formula has been constructed to represent them. When testosterone propionate was administered in increasing quantities for periods of weeks at each level, the volume of the prostate increased in a series of flattened curves. This volume, under the conditions mentioned, was found to stand in a simple arithmetic relationship to the amount of testosterone propionate administered. Moderate quantities of testosterone propionate masked the effects of small amounts of stilbestrol on the prostate. The reverse was also true and the critical amounts of these compounds were defined. The amounts of stilbestrol were determined which lowered the quantity of prostatic secretion resulting from the simultaneous administration of moderate amounts of testosterone propionate in castrate dogs, the result being a level and flat secretory curve which was maintained for many weeks. We designate this effect the plateau phenomenon. When this amount of estrogen was continued, and the dosage of testosterone propionate greatly augmented, the prostatic secretion did not increase in volume. Very slight increases above the critical amount of stilbestrol, however, caused the secretory curve to fall to new and still lower levels though the secretion was never completely suppressed. The acid phosphatase content of the prostatic secretion in the regions of secretory plateaus was similar to that of castrate dogs injected with androgen alone. The plateau phenomenon is due to simultaneous physiologic action of androgenic and estrogenic compounds on the prostatic cells. The depression of prostatic secretion resulting in the plateau phenomenon is due to both functional and structural changes in the prostatic epithelium. They are best explained on the assumption that differences in steroid threshold exist in groups of cells within the prostate, those of the anterior rim of the gland being least susceptible to estrogenic activity.

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GH gene expression in the submaxillary gland in normal and Ames dwarf mice

Journal of Endocrinology ◽

10.1677/joe.0.1690389 ◽

2001 ◽

Vol 169 (2) ◽

pp. 389-396 ◽

Cited By ~ 4

Author(s):

A Perez-Romero ◽

E Dialynas ◽

F Salame ◽

A Amores ◽

L Vidarte ◽

...

Keyword(s):

Southern Blot ◽

Submaxillary Gland ◽

Rt Pcr ◽

Submaxillary Glands ◽

Ames Dwarf Mice ◽

Igf I ◽

Ames Dwarf ◽

Heart Blood ◽

Two Parameters ◽

Dwarf Mice

High local GH-releasing hormone (GHRH) levels are capable of inducing transdifferentiation in salivary cells to synthesize GH. However, the factors implicated in this process remain unknown. To study this subject, normal and Ames dwarf mice were implanted in the submaxillary gland with a slow release pellet releasing 21 microgram GHRH (1-29)-NH(2)/day for 2 months. Control animals received placebo pellets at the same site. After 60 days, heart blood was collected and submaxillary glands were removed. Circulating levels of GH and IGF-I were significantly decreased (P<0.05) in dwarf mice in comparison with controls, and GHRH treatment did not modify either of these two parameters. Controls carrying GHRH pellets showed a significantly higher GH content (P<0.05) in the submaxillary gland than the placebo-treated normal mice. There were no differences between the IGF-I concentrations of placebo- and GHRH-treated salivary tissue from normal mice. Analysis of GH mRNA by RT-PCR followed by Southern blot revealed that GH transcripts were present in the salivary gland samples carrying the placebo pellets in both normal and dwarf mice. The expression of GH was significantly (P<0.05) increased by the GHRH pellets in salivary tissue from normal mice, but not in submaxillary glands from dwarf mice. Pit-1 mRNA was not detected in the GHRH-treated glands of normal and dwarf mice by RT-PCR or by Southern blot. Using these highly sensitive methods, we have been able to detect the transcription of both GH and Pit-1 in pituitaries from Pit-1-deficient Ames dwarf mice. The present experiment demonstrates that salivary tissue synthesizes GH when it is exposed to the influence of GHRH. Both basal and GHRH-induced salivary GH expression appear to be independent of Pit-1.

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Abstract 533: Lymph is a Vehicle for Extracellular Vesicles in Mice

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.36.suppl_1.533 ◽

2016 ◽

Vol 36 (suppl_1) ◽

Author(s):

Andreea Milasan ◽

Nicolas Tessandier ◽

Sisareuth Tan ◽

Alain Brisson ◽

Eric Boilard ◽

...

Keyword(s):

Extracellular Vesicles ◽

Biological Fluids ◽

Lymphatic Vessels ◽

The Body ◽

Artery Wall ◽

Waste Products ◽

Peripheral Tissues ◽

Cellular Debris ◽

Long Time ◽

Almost All

Introduction: Although for a long time considered as simple cellular debris, extracellular vesicles (EVs) are now known to be involved in many pathophysiological processes such as thrombosis, autoimmune diseases and inflammation. Due to their diversity and presence in different tissues, EVs are considered important biomarkers and thus, their precise detection in various biological fluids is important to better understand all their different functional activities. The lymphatic system works in close collaboration with the cardiovascular system to preserve fluid balance throughout the body. Lymphatic vessels are present in almost all vascularized tissues, including the brain and the artery wall, and their role in these organ-related pathologies are under intense investigations. Hypothesis: Since lymphatic vessels are often perceived as "sewers", due to their role in removing interstitial fluid and waste products from peripheral tissues such as the artery wall, we herein want to qualitatively and quantitatively assess the presence of EVs in circulating lymph. Methods and Results: Using several approaches such as a Zetasizer Nano S, electron microscopy and flow cytometry analysis, we have detected and characterized EVs in lymph of healthy animals, and found that these EVs are inclusively derived from red blood cells, platelets and lymphatic endothelial cells. Analysis of lymph from atherosclerotic mice (Ldlr -/- ) confirmed the idea that EVs number and origin varies according to the pathological setting. Conclusion: Herein, we show for the first time that EVs are present in lymph and that their level and origin vary in atherosclerosis. Our work will be setting the stage to a better understanding of the mechanism underlying EV accumulation in peripheral tissues during inflammation, and to better control related diseases.

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Analysis of elongating morphogenesis of quail anterior submaxillary gland: absence of localized cell proliferation

Development ◽

10.1242/dev.62.1.229 ◽

1981 ◽

Vol 62 (1) ◽

pp. 229-239

Author(s):

Hiroyuki Nogawa

Keyword(s):

Cell Proliferation ◽

Basement Membrane ◽

Regional Differences ◽

Submaxillary Gland ◽

Mesenchymal Cells ◽

Submaxillary Glands ◽

Parallel Direction ◽

Recombination Experiments

Quail anterior submaxillary glands elongated extensively without branching (more than sevenfold) from 8 to 10 incubation days. Investigation of mitotic activity of the rudiments in vivo showed no localized cell proliferation throughout the rudiments, and recombination experiments in vitro to examine regional differences in mitogenic activity of the surrounding mesenchyme also showed that no mesenchymal region specifically stimulates the epithelial cell proliferation. Histological observation of the rudiments showed that epithelial cells did not lengthen in a parallel direction to the long axis of the rudiment, and that mesenchymal cells encircled the epithelial cord perpendicularly to its axis. The basement membrane was obscure in the distal end of the rudiments, while it was easily detected in the other part of the rudiments. These results suggest that the elongating morphogenesis of the anterior submaxillary rudiments is not achieved by localized cell proliferation but by almost uniformly distributed cell proliferation, and mesenchymal cells surrounding the rudiment or the basement membrane may be involved in the controlling mechanisms of the elongating morphogenesis.

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Effect of adrenergic agonists on big and small renin

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1980.238.5.e416 ◽

1980 ◽

Vol 238 (5) ◽

pp. E416-E420

Author(s):

H. Iwao ◽

C. S. Lin ◽

A. M. Michelakis

Keyword(s):

Submaxillary Gland ◽

Plasma Renin ◽

Adrenergic Agonists ◽

Adrenergic Agonist ◽

Beta Adrenergic ◽

Molecular Weights ◽

Submaxillary Glands ◽

Beta Adrenergic Agonists ◽

Beta Adrenergic Agonist ◽

Alpha Adrenergic Agonist

The effect of alpha- and beta-adrenergic agonists on renal and submaxillary renin of different molecular weights was studied using male albino mice as experimental animals. Phenylephrine or isoproterenol was administered intravenously after removal of the submaxillary glands and/or kidneys. Renin was isolated from plasma by column chromatography and then measured by a direct radioimmunoassay. Phenylephrine increased both 68,500-dalton renin (big renin) and 38,000-dalton renin (small renin) in the plasma of nephrectomized mice. Isoproterenol increased big and small renin in the plasma of mice whose submaxillary glands were removed. In both cases, the increase of small renin was significantly greater than that of big renin. The results suggest that the alpha-adrenergic agonist phenylephrine affects the submaxillary gland, leading to the increase of both big and small plasma renin. In contrast, the beta-adrenergic agonist isoproterenol affects the kidney, leading to the increase of both big and small plasma renin.

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Heat acclimation and heat stress have different effects on cholinergic-induced calcium mobilization

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2001.280.6.r1688 ◽

2001 ◽

Vol 280 (6) ◽

pp. R1688-R1696 ◽

Cited By ~ 9

Author(s):

Pavel Kaspler ◽

Michal Horowitz

Keyword(s):

Heat Stress ◽

Submaxillary Gland ◽

Heat Acclimation ◽

Cytosolic Calcium ◽

Calcium Signal ◽

Permeabilized Cells ◽

Fura 2 ◽

Submaxillary Glands ◽

Intracellular Ca ◽

Glandular Cells

There is evidence that the signal transduction array responsible for the secretion of water in evaporative cooling by the submaxillary gland of the rat is subject to heat acclimatory responses. The objectives of the present study were 1) to examine whether heat acclimation affects intracellular Ca2+ mobilization and, in turn, submaxillary glandular responsiveness; 2) to assess whether the acclimatory responses differ from those evoked on heat stress (HS). Experiments were conducted on submaxillary glands of rats acclimated at 34°C for 0, 2 [short-term heat acclimation (STHA)], and 30 [long-term heat acclimation (LTHA)] days. The resting cytosolic calcium concentration ([Ca2+]c) and the carbamylcholine-evoked calcium signal ([Ca2+]s) of dispersed glandular cells were measured using the fluorescent dye fura 2 AM. Inositol-1,4,5-trisphosphate (IP3)-sensitive endoplasmic reticulum Ca2+ stores were determined in permeabilized cells using fura 2 potassium salt. STHA resulted in a drop in both [Ca2+]s and IP3-sensitive Ca2+ stores. On LTHA, the [Ca2+]samplitude reverted to the preacclimation value, whereas the IP3-sensitive Ca2+ stores remained low. The drop in [Ca2+]s on STHA is in accord with the decreased glandular output (measured by 86Rb efflux) observed during this acclimation phase. However, after LTHA the enhanced glandular output despite reduced [Ca2+]s levels suggests an increased efficiency of cellular secretory mechanisms in that group. Collectively, the alterations in [Ca2+]ssupport our biphasic acclimation model (Horowitz M, Kaspler P, Marmari Y, and Oron Y. J Appl Physiol 80: 77–85, 1996.). In nonacclimated glands, HS caused an elevation in [Ca2+]s coincidentally with a decrease in the IP3 Ca2+ stores. In contrast, [Ca2+]s in both STHA and LTHA glands was not affected by HS, despite a marked increase in the IP3-sensitive Ca2+ stores in the LTHA glands. The opposing responses to HS and heat acclimation in calcium signaling and stores confirm the specificity of each process.

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