GABAA receptor binding is transiently increased in rat whisker barrels during the second postnatal week, at a time when neurons in the developing rat cortex are vulnerable to excitotoxic effects. To test whether these GABAA receptors might serve to protect neurons from excessive excitatory input, polymer implants containing the GABAA receptor antagonist bicuculline were placed over barrel cortex for a 4-day period in young (postnatal days 8 - 12) and adult rats. In the cortex of young, but not adult rats, the chronic blockade of GABAA receptors resulted in substantial tissue loss and neuron loss. The greater loss of neurons in young rats supports the hypothesis that a high density of GABAA receptors protects neurons from excessive excitatory input during a sensitive period in development.

The use of animal models in research has led to a fierce debate between animal rights activists and scientists. The former claim that little useful information is gained from animal studies and the suffering of animals does not preclude any treatments which may be used to treat human illnesses. Yet, research scientists claim that in vivo animal models are of absolute necessity to developing treatments and cures to disease. To determine the necessity of animal use, one must examine the models currently in research. Have the animal models for disorders such as cystic fibrosis and muscular dystrophy given scientists enough information to develop effective treatments? This paper will examine the role of animal subjects in several disease research protocols, as well as the applicability of the research.

In this project a bacteria's ability to bind to human lung tissue was investigated. To carry out this study Pseudomonas aeruginosa, Eschericia coli and Burkholderia cepacia were used. B. cepacia served as the bacterium of interest. Isolating the gene which confers upon this bacterium the ability to bind to lung tissue was the main objective of this study. P. aeruginosa has been identified as being the bacteria most responsible for causing serious lung infections that can result in cystic fibrosis. This bacterium therefore served as the positive control in this study. On the contrary, E. coli does not possess this binding ability and served as the negative control. This paper gives a detailed outline of the different procedures necessary for the successful completion of this project. Firstly, a broad guideline of the important steps involved are explored. This is followed by a discussion on potential problems and possible solutions. Throughout the document, illustrations of expected results are indicated so as to further guide the researcher.

This dissertation research explored the capabilities of neuronal networks grown on substrate integrated microelectrode arrays in vitro with emphasis on utilizing such preparations in three specific application domains: pharmacology and drug development, biosensors and neurotoxicology, and the study of burst and synaptic mechanisms. Chapter 1 details the testing of seven novel AChE inhibitors, demonstrating that neuronal networks rapidly detect small molecular differences in closely related compounds, and reveal information about their probable physiological effects that are not attainable through biochemical characterization alone. Chapter 2 shows how neuronal networks may be used to classify and characterize an unknown compound. The compound, trimethylol propane phosphate (TMPP) elicited changes in network activity that resembled those induced by bicuculline, a known epileptogenic. Further work determined that TMPP produces its effects on network activity through a competitive inhibition of the GABAA receptor. This demonstrates that neuronal networks can provide rapid, reliable warning of the presence of toxic substances, and from the manner in which the spontaneous activity changes provide information on the class of compound present and its potential physiological effects. Additional simple pharmacological tests can provide valuable information on primary mechanisms involved in the altered neuronal network responses. Chapter 3 explores the effects produced …