We previously demonstrated that osmolality isotonic to the seminal plasma suppresses sperm motility in marine and freshwater teleosts, and exposure of sperm to hypertonicity of sea water or hypotonicity of fresh water, respectively, induces the initiation of sperm motility at spawning. The motile sperm became immotile by return of osmolality to the isotonic osmolality both in a marine teleost, ...

A prospective study was carried out on 50 patients (age 1-15 years) with nephrotic range of proteinuria to determine the correlation of 24-hour urinary total protein with spot urinary protein/creatinine ratio and urinary protein/osmolality ratio. Another 50 patients having no proteinuria grouped as control. Twenty-four hours urine and spot urine were collected from each child and were analyzed ...

Hyponatremia (serum sodium level less than 134 mmol/L) is a common electrolyte disturbance. Its high prevalence and potential neurologic sequelae make a logical and rigorous differential diagnosis mandatory before any therapeutic intervention. A history of concurrent illness and medication use as well as the assessment of extracellular volume status on physical examination may provide useful cl...

In this study, we demonstrate that two of the osmolytes utilized in the osmoconforming strategy of larval Culex tarsalis are regulated by two fundamentally different signals. When the external osmolality was increased using salinity (sea salts), hemolymph NaCl, proline and trehalose concentrations increased significantly. When sorbitol was used to increase the external osmolality without an ele...

The relation between cerebrospinal fluid (CSF) and serum osmolality was studied in 16 patients with hyperosmolar hypernatraemic dehydration before treatment. After correcting shock and acidosis, 0-45% saline in 2-5 or 5% dextrose was infused in each patient over a 48- to 72-hour period. During rehydration, serum osmolality, electrolyte concentrations, urea nitrogen, and blood pH were measured s...

A mathematical model was used to investigate how concentrated urine is produced within the medullary cones of the quail kidney. Model simulations were consistent with a concentrating mechanism based on single-solute countercurrent multiplication and on NaCl cycling from ascending to descending limbs of loops of Henle. The model predicted a urine-to-plasma (U/P) osmolality ratio of approximately...

Water channel aquaporin-1 (AQP1) is strongly expressed in kidney in proximal tubule and descending limb of Henle epithelia and in vasa recta endothelia. The grossly normal phenotype in human subjects deficient in AQP1 (Colton null blood group) and in AQP4 knockout mice has suggested that aquaporins (other than the vasopressin-regulated water channel AQP2) may not be important in mammalian physi...

It has become widely accepted that the osmolality gradient along the corticomedullary axis of the mammalian outer medulla is generated and sustained by a process of countercurrent multiplication: active NaCl absorption from thick ascending limbs is coupled with the counterflow configuration of the descending and ascending limbs of the loops of Henle to generate an axial osmolality gradient alon...

SCHMIDT-NIELSEN, BODIL, AND ERIK SKADHAUGE, Function of the excretory system of the crocodile (Crocodylus acutus) Am. ,T. Physiol. 212(5): 973-980. I 967 .-Glomerular filtration rate (GFR), tubular and cloaca1 functions were studied, during normal conditions, water loading, salt loading, and isosmotic expansion of the extracellular fluid volume. Na+, K+, Cl-, NH& and osmolality were determined ...

Received September 29, 2003 Abstract The objective of this retrospective study is to evaluate the effectiveness of using early morning urine osmolality as a predictor of response to oral desmopressin in children with primary monosymptomatic nocturnal enuresis. Children treated solely with oral desmopressin for primary monosymptomatic nocturnal enuresis, between the period of January 1997 and Ju...