scholarly journals Excretion by the Malpighian Tubules of the Stick Insect, Dixippus Morosus (Orthoptera, Phasmidae): Calcium, Magnesium, Chloride, Phosphate and Hydrogen Ions

1956 ◽  
Vol 33 (4) ◽  
pp. 697-708
Author(s):  
J. A. RAMSAY
Keyword(s):  
General Problem ◽  
Magnesium Chloride ◽  
Liquid Paraffin ◽  
Stick Insect ◽  
Urine Flow ◽  
Malpighian Tubules ◽  
Hydrogen Ions ◽  
Calcium Magnesium

1. The excretion of calcium, magnesium, chloride, phosphate and hydrogen ions has been studied in preparations of single Malpighian tubules isolated in drops of serum under liquid paraffin. 2. The concentrations of calcium, magnesium and chloride are always lower in the urine than in the serum. 3. The concentration of phosphate is always greater in the urine than in the serum. As the concentration of phosphate in the serum increases, the rate of urine flow also increases. 4. The urine is always alkaline to the serum but becomes acid in the rectum. 5. The general problem of excretion by Malpighian tubules is briefly reviewed and discussed.

The Excretion of Sodium, Potassium and Water by the Malpighian Tubules of the Stick inSect, Dixippus Morosus (Orthoptera, Phasmidae)

1955 ◽  
Vol 32 (1) ◽  
pp. 200-216 ◽  
Author(s):  
J. A. RAMSAY
Keyword(s):  
Potassium Concentration ◽  
Physiological Activity ◽  
Liquid Paraffin ◽  
Stick Insect ◽  
Proximal Region ◽  
Malpighian Tubules ◽  
Electrochemical Gradient ◽  
Sodium Potassium ◽  
Single Tubules ◽  
Sodium And Potassium

1. The excretion of sodium, potassium and water by the Malpighian tubules of the stick insect has been further studied in preparations of single tubules isolated in droplets of medium under liquid paraffin. 2. There is some gradation of physiological activity along the length of the superior tubule. Sodium, potassium and water are secreted into the tubule at all levels, but the sodium/potassium ratio is greater in the proximal region. 3. The proximal and middle regions of the inferior tubule have not been shown to differ in any way from the corresponding regions of the superior tubule. The distal dilatation has quite different properties and does not produce urine. 4. The rate of urine flow increases markedly as the potassium concentration in the medium is increased; the corresponding effect of sodium is barely detectable. 5. Sodium, like potassium, can be actively transported against an electrochemical gradient, and does not appear to compete with potassium in the secretory mechanism. 6. The rates of secretion of sodium and potassium vary in direct proportion to the respective concentrations of these ions in the medium. The rate of secretion of potassium is more than ten times greater than that of sodium.

Active Transport of Water by the Malpighian Tubules of the Stick Insect, Dixippus Morosus (Orthoptera, Phasmidae)

1954 ◽  
Vol 31 (1) ◽  
pp. 104-113 ◽  
Author(s):  
J. A. RAMSAY
Keyword(s):  
Osmotic Pressure ◽  
Active Transport ◽  
Liquid Paraffin ◽  
Stick Insect ◽  
Malpighian Tubules ◽  
Normal Rate ◽  
Urine Production

1. Single Malpighian tubules of the stick insect have been studied as preparations isolated in drops of haemolymph under liquid paraffin. Measurements of osmotic pressure have been made on haemolymph and urine. 2. The urine is more or less isotonic with the haemolymph over a wide (45-145%) range of osmotic pressure. But in a majority of cases the urine is slightly but significantly hypotonic to the haemolymph. 3. From these and other observations it is concluded that water must be actively transported across the wall of the tubule. The implications of this conclusion are discussed. 4. The normal rate of urine production is of the order of 0.07 x 1o-3 cu.mm./sq.mm./min. The rate increases with increasing dilution of the haemolymph and vice versa. 5. Urine production normally ceases, probably as a result of distension of the tubule, when the pressure in the lumen rises to about 20 cm. H2O.

Hormonal Control of the Malpighian Tubules of the Stick Insect, Carausius Morosus

1970 ◽  
Vol 52 (3) ◽  
pp. 653-665 ◽  
Author(s):  
DIANA E. M. PILCHER
Keyword(s):  
Stick Insect ◽  
Hormonal Control ◽  
The State ◽  
Malpighian Tubules ◽  
Suboesophageal Ganglion ◽  
Carausius Morosus ◽  
Corpora Cardiaca ◽  
Diuretic Hormone ◽  
The Brain

1. Urine secretion by isolated Malpighian tubules of Carausius is accelerated by a diuretic hormone which can be extracted from the brain, corpora cardiaca and suboesophageal ganglion. 2. The level of this hormone in the haemolymph varies according to the state of hydration of the insect. 3. The hormone is inactivated by the tubules, and a mechanism is proposed whereby the tubules might be controlled by the hormone in vivo.

The Physiology of Excretion in the Cotton Stainer, Dysdercus Fasciatus, Signoret

1966 ◽  
Vol 44 (3) ◽  
pp. 553-566
Author(s):  
M. J. BERRIDGE
Keyword(s):  
Osmotic Pressure ◽  
Urine Flow ◽  
Malpighian Tubules ◽  
Hormone Concentration ◽  
Serum Dilution ◽  
Wide Range ◽  
Tentative Hypothesis ◽  
Cotton Stainer ◽  
Urine Formation ◽  
Different Parts

1. The preparation of isolated Malpighian tubules is described. The rate of urine flow increases with increasing serum dilution, and vice versa. Urine is almost isotonic with haemolymph over a wide range of osmotic pressure. 2. Serum collected from 3-day-old insects promotes urine formation, whereas that from 6-day-old insects does not. 3. A factor which was extracted from the m.n.c. accelerates the rate of urine flow, from a normal value of 0·87 to 3·1 mm.3 x 10- 3/min. The osmotic pressure of the urine, however, remains unchanged. 4. The hormone concentration of different parts of the nervous system was assayed with these isolated tubules. Most activity occurs in the m.n.c., but some activity is present in extracts from the c.c. and the fused ganglionic mass in the mesothorax. 5. Malpighian tubules isolated from 6-day-old insects remain inactive, but after the addition of hormone they immediately begin to produce urine. 6. These observations have been incorporated into a tentative hypothesis on the control of excretion in Dysdercus.

Induction of potential for sperm motility by bicarbonate and pH in rainbow trout and chum salmon

1988 ◽  
Vol 136 (1) ◽  
pp. 13-22 ◽  
Author(s):  
S. Morisawa ◽  
M. Morisawa
Keyword(s):  
Rainbow Trout ◽  
Seminal Plasma ◽  
Magnesium Chloride ◽  
Chum Salmon ◽  
Ph Value ◽  
Bicarbonate Concentration ◽  
Sodium Potassium ◽  
Sperm Duct ◽  
Calcium Magnesium ◽  
Immotile Spermatozoa

Spermatozoa of rainbow trout and chum salmon, which have no potential for motility in the testis, acquire that potential in the sperm duct. This paper demonstrates that there is little difference between the levels of sodium, potassium, calcium, magnesium, chloride and osmolality of the seminal plasma in the testis and in the sperm duct. However, the bicarbonate concentration of the seminal plasma and the pH value of semen were higher in the sperm duct than in the testis. When immotile spermatozoa obtained from the testis were incubated in artificial seminal plasma with a high pH and containing HCO3-, spermatozoa became motile within 1 h. These results suggest that spermatozoa of salmonid fish acquire the potential for motility as a result of the increase in seminal bicarbonate concentration and pH that occurs as spermatozoa pass from the testis to the sperm duct.

Memoirs: The Embryonic Development of the Stick-Insect, Carausius morosus

1936 ◽  
Vol s2-78 (311) ◽  
pp. 487-511
Author(s):  
A. J. THOMAS
Keyword(s):  
Embryonic Development ◽  
Stick Insect ◽  
Malpighian Tubules ◽  
Germ Band ◽  
Ventral Plate ◽  
Carausius Morosus ◽  
Gut Epithelium ◽  
Cleavage Nucleus ◽  
Endodermal Cells ◽  
Late Stages

1. The maturation of the egg takes place in the ovarian tube, and is immediately followed by the formation of the cleavagenucleus and its division into many nuclei. 2. The entire products of the cleavage-nucleus migrate to the surface to form the blastoderm. Cleavage of the yolk was not observed even in late stages. Yolk-cells are absent when the blastoderm is being formed. 3. Primitive endodermal cells are proliferated from the middle of the germ-band, and form a membrane between the germ-band and the yolk. The membrane is present only in embryonic stages; some of the cells proliferated wander into the yolk and act as vitellophags. 4. Mesoderm is formed by proliferation of cells from the ventral plate. It is preceded by the formation of a shallow gastrular furrow, and from the bottom of this furrow proliferation takes place. The mesoderm becomes arranged in segmental masses. 5. Two masses of cells proliferated at the anterior and posterior ends of the germ-band are shown to be the endodermal rudiments from which the mid-gut epithelium is formed. The invaginations of the stomodaeum and proctodaeum grow against these masses and carry parts of the proliferating areas near their blind ends. It is shown that the various methods of mid-gut formation which have been described could be reconciled with the process described in Carausius. 6. The hinder end of the mid-gut is flanked by two plates of ectoderm which are forward extensions of the proctodaeum. Into these extensions the Malpighian tubules open, and, as their histology is identical with that of these extensions and widely different from that of the mid-gut, these tubules must be ectodermal in nature. 7. The formation of the amnion and serosa are described.

scholarly journals THE SOLUBILITY AND PROPERTIES OF A PURIFIED ICHTHYOCOL IN SALT SOLUTIONS OF NEUTRAL pH

1957 ◽  
Vol 3 (4) ◽  
pp. 545-557 ◽  
Author(s):  
Paul M. Gallop ◽  
Sam Seifter ◽  
Edward Meilman
Keyword(s):  
Calcium Chloride ◽  
Magnesium Chloride ◽  
Divalent Cations ◽  
Optical Rotation ◽  
Sodium Thiosulfate ◽  
Salt Solutions ◽  
Bacterial Collagenase ◽  
Neutral Ph ◽  
Calcium Magnesium ◽  
Intermediate Concentration

1. Purified citrate-extracted ichthyocol obtained from carp swim bladders has been further characterized with respect to its content of certain amino acids and carbohydrate substances. 2. The degree of solubilization or dispersion of ichthyocol by solutions of certain salts maintained in the range of neutral pH and at a temperature of 0–2°C. has been determined. 3. While a number of salts of monovalent cations had no significant solubilizing effects on ichthyocol, ammonium chloride in a concentration of 1 M did cause solution of the protein. 4. Sodium thiosulfate in a range of concentrations caused the solubilization of ichthyocol but was most effective in an intermediate concentration of 0.25 M. 5. Several salts of divalent cations, in particular the chlorides of calcium, magnesium, and barium, and magnesium thiosulfate in concentrations ranging from 0.3 to 1 M caused the immediate and complete solubilization of the ichthyocol. 6. Solutions of ichthyocol in calcium chloride, magnesium chloride, and sodium thiosulfate buffered or adjusted to pH 7.0, were studied with respect to intrinsic viscosity of the protein, optical rotation, ultracentrifugal sedimentation, and reconstitution into fibers. It was found in each case that the original characteristics of the collagen, as determined previously in acid solution, were maintained when the protein was dissolved in salt solutions of neutral pH. No evidence of denaturation or gelatinization could be found when ichthyocol was solubilized under the stated conditions. 7. Collagen in neutral solution with sodium thiosulfate, calcium chloride, or magnesium chloride was not attacked by trypsin as determined viscometrically at 20.0°C., but was rapidly degraded by a purified bacterial collagenase.

The comparative effects of exchangeable calcium, magnesium, and sodium on some physical properties of red-brown earth subsoils. III. The permeability of Shepparton soil and comparison of methods

Soil Research ◽  
1973 ◽  
Vol 11 (2) ◽  
pp. 159 ◽  
Author(s):  
AC Bakker ◽  
WW Emerson
Keyword(s):  
Flow Rate ◽  
Divalent Cation ◽  
Magnesium Chloride ◽  
Aggregate Stability ◽  
Viscous Drag ◽  
Comparison Of Methods ◽  
Soluble Salts ◽  
Initial Flow ◽  
Calcium Magnesium ◽  
Water Transmission

Beds of aggregates of Shepparton soil were leached with calcium chloride or magnesium chloride or with chloride solutions of given SAR with either calcium or magnesium as the complementary cation to bring the aggregates to a known ESP within the range 2.6-5.2. The last solution was 1 mM in the divalent cation. Water was then allowed to flow slowly through and the decrease in the flow rate measured. The permeability of aggregate beds washed with calcium or magnesium showed only a negligible decrease with time. With sodium present, the rate of decrease for a given ESP was faster the greater the initial flow rate of the water and also for smallersized aggregates. The ESP required to produce a given decrease in flow rate was reduced when magnesium was the complementary cation rather than calcium. The flow patterns are explained in terms of the rate of dispersion of clay from the aggregates in sympathy with the rate of loss of soluble salts, rather than detachment due to viscous drag. Four methods of measuring aggregate stability in water have been described in this series of papers. Their possible use to predict whether sodium in conjunction with magnesium will reduce water transmission through subsoils compared with similar calcium soils is discussed.

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