Tamm-Horsfall glycoprotein binds IgG with high affinity.

Tamm-Horsfall protein (THP), a monomeric glycoprotein (M(r) 80 to 100 kDa), is produced by the mammalian kidney's thick ascending limb of Henle cells and excreted into the urine. The function of THP is uncertain. Here we report that a high molecular weight contaminant in sheep THP (sTHP) preparations was identified as sheep IgG by its positive reaction with donkey anti-sheep IgG antibody and with protein G.

Cation-induced aggregation of cat Tamm-Horsfall glycoprotein and its possible role in feline urolithiasis.

The in vitro cation-induced aggregation properties of cat Tamm-Horsfall protein (cTHP), a urinary glycoprotein, were examined and related to the potential role of cTHP in feline urolithiasis. The aggregation assay involved adding either CaCl2, MgCl2, or NaCl to solutions containing purified cTHP, and then separating the aggregated cTHP by centrifugation. The concentration of cTHP remaining in the supernatant was quantified using a previously developed enzyme-linked immunosorbent assay (ELISA).

Urinary Tamm-Horsfall glycoprotein concentrations in normal and urolithiasis-affected male cats determined by an ELISA.

A precise and reproducible enzyme-linked immunosorbent assay (ELISA) which measures urinary cat Tamm-Horsfall glycoprotein (cTHP) was developed in order to investigate the possible role of cTHP in the pathogenesis of feline urolithiasis. Reproducible quantification required that the cTHP be disaggregated with 2M urea and 0.05% Tween 20.

Dermal extracellular lipid in birds.

A light and electron microscopic study of the skin of domestic chickens, seagulls, and antarctic penguins revealed abundant extracellular dermal lipid and intracellular epidermal lipid. Dermal lipid appeared ultrastructurally as extracellular droplets varying from less than 1 micron to more than 25 microns in diameter. The droplets were often irregularly contoured, sometimes round, and of relatively low electron density.

Rubratoxin B mycotoxicosis in the Syrian hamster: ultrastructural alterations.

Rubratoxin B was given to Syrian hamsters as a single intraperitoneal dose of 0.4 mg/kg. Hamsters were killed at 1, 2, 4, and 6 hr after dosing, and the kidneys and liver were fixed by intravascular perfusion.

Citrinin mycotoxicosis in the rabbit: ultrastructural alterations.

Citrinin was given to rabbits as a single oral dose of 120 or 67 mg/kg. Rabbits were killed at 4, 6, 8, 10, and 12 hours post dosing, and the kidneys were fixed by intravascular perfusion. Ultrastructural alterations were evident by 4 hours after treatment.

Ultrastructural ocular lesions of 6-aminonicotinamide toxicosis in rabbits.

6-Aminonicotinamide, given by intraperitoneal injection to male and female Dutch belted rabbits, produced swelling and vacuolation of ciliary and iridal epithelium plus vacuolation of the retinal pigment epithelial and outer plexiform layers of the retina. By transmission electron microscopy, inner and outer ciliary epithelial cells and inner iridal epithelial cells contained numerous coalescing, membrane-bound vacuoles of the cytocavitary network. These vacuoles were viewed as numerous interconnecting, intracytoplasmic cavities in scanning electron micrographs.

Pathology of 6-aminonicotinamide toxicosis in the rabbit.

Daily doses of 6-aminonicotinamide (3-5 mg/kg) given by ip injection produced ataxia of the hind limbs progressing to an ascending paresis/paralysis, anorexia, diarrhoea and death in male and female New Zealand White and Dutch Belted rabbits. At autopsy, caecal and gastric distention were seen and the apex of the gall bladder had necrotic foci. Light microscopic lesions included atrophy and necrosis of the white lobe of Harder's gland and atrophy of seminiferous tubules with cellular necrosis, vacuolation and the presence of multinucleated giant cells.

Single intravenous and multiple intramuscular dose pharmacokinetics and tissue residue profile of gentamicin in sheep.

Single and multiple dose gentamicin regimens were compared in sheep to determine the relevant pharmacokinetic differences. Seven mature sheep were given 10 mg/kg of gentamicin by IV bolus. Serum concentrations were monitored for 19 days.

Species dependent gentamicin pharmacokinetics and nephrotoxicity in the young horse.

Gentamicin pharmacokinetics and nephrotoxic potential were evaluated in twelve 2 to 3 month-old horses. Whereas recent evidence in our clinic indicated that young horses may be especially susceptible to gentamicin nephrotoxicity, young rabbits and rats are usually resistant. Gentamicin (4.

Case study of a diabetic dog with chronic membranous glomerulopathy treated with continuous intraperitoneal insulin infusion.

The purpose of this study was to determine the use of continuous intraperitoneal insulin infusion over an extended period (in maintaining metabolic control) and to evaluate the benefits of this treatment in reversing the kidney pathology of a chronic diabetic dog with membranous glomerulopathy. Hyperglycemia was eliminated, but reevaluations of the insulin infusion pattern were necessary. An initial kidney biopsy revealed fusion of the foot processes, thickening of the basement membrane, and subendothelial deposition.

Single dose gentamicin nephrotoxicity in the dog: early functional and ultrastructural changes.

A single dose (15mg/kg) of the aminoglycoside antibiotic gentamicin was administered intravenously to 4 purebred 5-month old beagles. Six 24-hour creatinine, urea, phosphate, sodium, and potassium clearances were performed, three before and three after gentamicin infusions, as were hematology and urinalysis. Animals were necropsied on the fourth day after drug infusion.

Gentamicin pharmacokinetic changes in induced acute canine nephrotoxic glomerulonephritis.

Most clinical schemes used to adjust gentamicin dosage regimens in renal insufficiency assume that the volume of distribution remains constant. The purpose of this investigation was to determine the pharmacokinetic parameters of gentamicin (two-compartment open model) before and at two points during the acute phase of experimentally induced nephrotoxic (injection of anti-glomerular basement membrane antibody) glomerulonephritis in beagle dogs. Disease was verified by decreased 24-h creatinine clearance, increased 24-h urinary protein excretion, and characteristic immunofluorescent, light- and electron-microscopic lesions.

Polyvinyl alcohol toxicosis as a model of glomerulonephritis in Beagle dogs.

Investigation of pharmacokinetics of certain drugs in experimental models of glomerulonephritis would facilitate development of dose schedules for dogs with this disease. Polymerized polyvinyl alcohol (PVA)-induced glomerulonephritis was investigated in healthy, 15-week-old purebred Beagle dogs. Three dogs were injected daily with 20 ml of 5% (w/v) PVA (125,000 molecular weight, 88% hydrolyzed) in phosphate-buffered saline solution.

Ultrastructure of timed isolates of in vitro canine articular chondrocytes.

Articular chondrocytes were enzymatically isolated from the distal end of the adult canine femur. The digestion procedure was conducted for 2- or 6-hour intervals, using 0.25% trypsin and 0.

The fine structure of lipofuscin in the mouse hippocampus.

Lipofuscin was ultrastructurally evaluated in the hippocampus of C57B1/6 male mice at 8, 14, 20 and 24 months of age. The mice were anesthetized, perfused intracardially with 3% glutaraldhyde, and routinely processed for transmission electron microscopic evaluation. Lipofuscin was found in the hippocampus of mice of all age groups.

Ochratoxin A and citrinin induced nephrosis in Beagle dogs. III. Terminal renal ultrastructural alterations.

The extent and type of renal ultrastructural changes in Beagle dogs varied with the administration of ochratoxin A and citrinin alone and in the two dosage combinations. The three predominant changes were cytoplasmic vacuolation, myelin figure formation and lesions designated as cytoplasmic disarray. These changes were mainly of the endomembane system of the tubular epithelial cells.

Alterations in the hippocampus of aged mice.

The hippocampus of C57B1/6 mice was examined histologically and electron microscopically. Male and female mice at 3 and 8 months of age and female mice at 16 months of age were studied. PAS positive foci, containing particles 1-2 mu in diameter, were observed in the hippocampal region of 8 and 16 month old mice.

Neuronal-visceral GM1 gangliosidosis in a dog with beta-galactosidase deficiency.

A 9-month-old dog with a history of progressive motor dysfunction was shown to have a deficiency in brain beta-galactosidase activity. The canine disease, like that of children with GM1 gangliosidosis, is characterized by accumulation of GM1 ganglioside in the brain, liver, and spleen, and membranous cytoplasmic bodies in neurons. The dog's pedigree suggests an autosomal recessive pattern of inheritance.

Morphological characteristics of dendrite bundles in the lumbar spinal cord of the rat.

The finding of motoneuron dendrites organized into small compact bundles in cats, monkeys and pigs suggested that a study of this phenomenon in rats should be undertaken. An analysis was performed with electron microscopy, light microscopy and Golgi methods. An extensive dendrite bundle organization was found in the sixth lumbar segment of the spinal cord.

Caliber spectra of fibers in the fasciculus gracilis of the cat cervical spinal cord: a quantitative electron microscopic study.

In order to obtain a better understanding of the microscopic structure of the cat fasciculus gracilis, entire cross-sections of the fasciculus were examined with the electron microscope. Twenty-five thousand, two hundred and eighty-four fibers were encountered in one fasciculus. The fiber caliber spectra obtained from the study show that the fasciculus gracilis at cervical level has a unique fiber distribution pattern.