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Full-Text Articles in Veterinary Toxicology and Pharmacology

Microtransplantation Of Rat Brain Neurolemma Into Xenopus Laevis Oocytes To Study The Effect Of Environmental Toxicants On Endogenous Voltage-Sensitive Ion Channels, Edwin Murenzi Jul 2017

Microtransplantation Of Rat Brain Neurolemma Into Xenopus Laevis Oocytes To Study The Effect Of Environmental Toxicants On Endogenous Voltage-Sensitive Ion Channels, Edwin Murenzi

Masters Theses

Microtransplantation of mammalian neurolemma into Xenopus laevis oocytes has been used to study ion channels in terms of their structure and function in the central nervous system. Use of microtransplanted neurolemma is advantageous in that tissue can be obtained from various sources, ion channels and receptors are present in their native configuration and they can be used to evaluate numerous channelpathies caused by environmental toxicants. Here we show that Xenopus oocytes injected with fragments of rat brain neurolemma successfully express functional native ion channels that are assembled in their own plasma membrane. Using a high throughput two electrode voltage clamp …


The Toxicity Of Acetaminophen, Caffeine And Carbendazim In Earthworms (Eisenia Fetida), Matthew M. Bulman Jan 2012

The Toxicity Of Acetaminophen, Caffeine And Carbendazim In Earthworms (Eisenia Fetida), Matthew M. Bulman

Masters Theses

There has been a need for the assessment of ground water contamination risk on terrestrial organisms. One terrestrial organism, Eisenia fetida, was chosen as a test species and exposed to three common pharmaceutical and/or pesticide related contaminants: acetaminophen (CAS#103-90-2), caffeine (CAS#58-08-2) and carbendazim (CAS#10605-21-7), respectively. Levels of contamination varied from grams per liter to micrograms per liter (ppb) using distilled water as the solvent. Eisenia fetida was examined through a 28 day range/index toxicity test. A Benchmark Dose (BMD) dichotomous probit analysis, using a 95% confidence interval, was calculated for all three contaminants. All three contaminants were found to have …


Effects Of Methylxanthines On Newborn Rat Respiration, Craig Gatto Jan 1989

Effects Of Methylxanthines On Newborn Rat Respiration, Craig Gatto

Masters Theses

Methylxanthines (MX), such as theophylline, are commonly used in the treatment of recurrent apnea due to their stimulant effects on the respiratory center. Structure-activity studies have demonstrated that substitution of alkyl groups on the 3-position of the xanthine nucleus results in increased bronchodilator potency, while substitution on the 1-position is important for adenosine antagonism and CNS stimulation. Three different alkylxanthines were studied to determine the structural requirements for respiratory stimulation. Respiratory rates and volumes were determined in 4- to 7-day-old rats using a volume displacement body plethysmograph. Measurements were made before and at 5 minute intervals after subcutaneous (s.c.) injection …


The Effects Of Xanthine And Adenosine Analogs On Rat Pup Diaphragmatic Contractility, Liam C. Farrell Jan 1987

The Effects Of Xanthine And Adenosine Analogs On Rat Pup Diaphragmatic Contractility, Liam C. Farrell

Masters Theses

Methylxanthines are commonly used in the treatment of respiratory disorders such as asthma, apnea of prematurity and Cheyne-Stokes respiration. Recently, certain methylxanthines have been found to potentiate the contraction of the diaphragm and increase contraction strength of the fatigued diaphragm. The mechanism of action of the methylxanthines is unknown. Three theories have been proposed but each has its supportive and negative points. One theory is that methylxanthines inhibit cyclic AMP phosphodiesterase (PDE) which facilitates contraction by increasing cyclic AMP levels in the cell. Another theory is that methylxanthines antagonize adenosine, thus blocking the adenosine-induced inhibition of contraction. The third theory …


Treflan And The Oxygen Consumption Of Green Sunfish (Lepomis Cyanellus), Barbara Jo Warner Jan 1975

Treflan And The Oxygen Consumption Of Green Sunfish (Lepomis Cyanellus), Barbara Jo Warner

Masters Theses

Oxygen consumption rates of 51 green sunfish (Lepomis cyanellus, Rafinesque) were monitored over five hours exposure to Treflan E.C. concentrations of 0, 0.32, 0.56, 1.0, and 2.0 ppm. There was a great variation in the responses of the fish at each concentration; and Student's t-tests revealed no significant differences. However, graphs of the mean hourly oxygen consumption rates showed certain trends. During the fifth hour of exposure, there appears to be an acclimation to the Treflan at concentrations of 0.32 and 0.56 ppm; but no such acclimation at the higher concentrations of 1.0 and 2.0 ppm. Hourly oxygen …


An Investigation Of The Behavioral Effects Of Methylphenidate Hydrochloride On Schedule-Induced Polydipsia In Rats, Linda Sederquist Smith Jan 1975

An Investigation Of The Behavioral Effects Of Methylphenidate Hydrochloride On Schedule-Induced Polydipsia In Rats, Linda Sederquist Smith

Masters Theses

The influence of methylphenidate hydrochloride injections on six male Charles River rats displaying schedule induced polydipsia was examined in this study. Bar pressing, licking, and water consumption were measured during a total of 63 daily one hour trials conducted with a variable interval 60-second schedule of bar pressing for pellets with water constantly available. The polydipsic response was acquired by subjects during the first 28 trials. Subjects were then divided into experimental and control groups. The experimental subjects recieved a 1 mg/kg injection of methylphenidate prior to regular trials 29-49 and extinction trials 50-63. Control subjects were injected with a …


Pesticide Residues In The Illinois Wild Turkey, John M. Bridges Jan 1975

Pesticide Residues In The Illinois Wild Turkey, John M. Bridges

Masters Theses

Adipose tissue from 55 turkeys, killed during the 1974 hunting season in southern Illinois, was grouped by age and location of the birds, and the pesticide concentrations in them were determined by gas/liquid chromatography. Twelve different pesticides were identified in the samples with only four, total DDT, heptachlor epoxide, toxaphene, and linuron, being present in all samples. Concentrations ranged from 0.02 ppm to 0.88 ppm.