vii, 332 leaves : ill., tables ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Human Physiology, 1978

Thesis (Ph.D.) -- University of Adelaide, Department of Human Physiology, 1978.

A cDNA sequence representing a <i> Brassica carinata</i> gene the expression of which is induced by copper chloride treatment, was isolated from a library constructed with mRNA from treated leaves, and designated CIL1 (COPPER CHLORIDE INDUCED in LEAVES). A Basic Local Alignment Search Tool search revealed that CIL1 has similarities to an auxin-induced gene, AIR12 from <i>Arabidopsis thaliana</i>. Southern blot analysis of CIL1 in <i>B. carinata, B. nigra</i> and <i>B. oleracea</i> indicated that it is a member of a small multigene family. Antisense CIL1 transgenic plants were generated to investigate the function of CIL1, and the resulting transformants displayed increased secondary branching suggesting that CIL1 has a role in regulating hormone content or plant architecture. Results of induction studies indicate that the auxin analog a-naphthalene acetic acid, the cytokinin 6-benzylaminopurine, and +/- abscisic acid increase expression of CIL1. Seven CIL1 antisense lines were grown to the T4 generation and were confirmed homozygous. Analysis of CIL1 expression using real-time quantitative RT-PCR showed reduced expression in every examined line. Transgenic plants produced many leaves at the lateral meristems indicating a release of apical dominance. Additionally, the concentrations of auxins, cytokinins, and abscisic acid were altered in the roots and stems of transgenic plants compared to non-transformed plants. Therefore, CIL1 has a role in regulating hormone content that affects lateral meristem activity, apical dominance, and leaf production.

A cDNA sequence representing a <i> Brassica carinata</i> gene the expression of which is induced by copper chloride treatment, was isolated from a library constructed with mRNA from treated leaves, and designated CIL1 (COPPER CHLORIDE INDUCED in LEAVES). A Basic Local Alignment Search Tool search revealed that CIL1 has similarities to an auxin-induced gene, AIR12 from <i>Arabidopsis thaliana</i>. Southern blot analysis of CIL1 in <i>B. carinata, B. nigra</i> and <i>B. oleracea</i> indicated that it is a member of a small multigene family. Antisense CIL1 transgenic plants were generated to investigate the function of CIL1, and the resulting transformants displayed increased secondary branching suggesting that CIL1 has a role in regulating hormone content or plant architecture. Results of induction studies indicate that the auxin analog a-naphthalene acetic acid, the cytokinin 6-benzylaminopurine, and +/- abscisic acid increase expression of CIL1. Seven CIL1 antisense lines were grown to the T4 generation and were confirmed homozygous. Analysis of CIL1 expression using real-time quantitative RT-PCR showed reduced expression in every examined line. Transgenic plants produced many leaves at the lateral meristems indicating a release of apical dominance. Additionally, the concentrations of auxins, cytokinins, and abscisic acid were altered in the roots and stems of transgenic plants compared to non-transformed plants. Therefore, CIL1 has a role in regulating hormone content that affects lateral meristem activity, apical dominance, and leaf production.

Thesis (Ph.D.) Dept. of physiology and Pharmacology, University of Adelaide, 1975. / Typescript (photocopy).

Zugl.: München, Univ., Diss., 2007

The present studies explore binding, distribution, and function of angiotensin II (AII) receptors (AT$\sb1$ and AT$\sb2)$ in the brain. The discovery that sulfhydryl reducing agents masked some but not all AII receptors in the brain prompts an evaluation of commonly used binding assay buffer constituents. EDTA enhances binding (40%) at both AT$\sb1$ and AT$\sb2$ nuclei, while bacitracin did not alter binding at either receptor subtype. Phenanthroline and BSA differentially altered binding at AT1 (220% of control) and AT$\sb2$ (118% of control) receptors. The results indicate that phenanthroline and BSA would be poor buffer constituents for studies comparing binding at AT$\sb1$ and AT$\sb2$ receptors. All receptors were mapped in normotensive and genetically hypertensive hamster brains and the subtype composition estimated for a number of brain nuclei and the pituitary. Binding in the hamster was similar to that previously observed in the rat brain with exceptions: (1) additional binding in the medial habenula and interpeduncular nuclei, (2) absence of binding in the inferior olive, suprachiasmatic nucleus, medial amygdala, piriform cortex, and subthalamic nucleus and (3) quantitative differences in the dorsomotor nucleus of the vagus, striatum, hippocampus and anterior pituitary. Unlike studies of the normotensive and spontaneously hypertensive rat, we found no significant differences in binding distribution, density or subtype composition when comparing normal and genetically hypertensive hamsters. Finally, the effects of brain angiotensin II (AII) on central catecholamine utilization were determined. We found no significant differences in norepinephrine, epinephrine or dopamine utilization in rat brain homogenates following intracerebroventricular injection of AII. Although there is evidence that AII alters catecholamine utilization in some brain nuclei, these alterations appear limited (anatomically and/or quantitatively) to a relatively small portion of the brain catecholaminergic system. The results indicate that the selection of buffer constituents is an important consideration for AII binding studies, that there are minor species differences in the distribution of AII receptors in the brain and that despite substantial functional and anatomical overlap, only a relatively small portion of the brain catecholaminergic system is modulated by angiotensin II.

AN ABSTRACT OF THE THESIS OF Crystal Marie Welsh, for the Masters of Science degree in Equine Reproductive Physiology, presented on October 6, 2009, at Southern Illinois University Carbondale. TITLE: IMMUNOHISTOCHEMICAL IDENTIFICATION OF DOPAMINERGIC AND ADRENERGIC NERVES IN THE EQUINE OVARY MAJOR PROFESSOR: Dr. Sheryl S. King Dopamine (DA) appears to play a role in seasonal reproduction in the mare. We hypothesize that DA is delivered to the ovary by nerves. The objective of this study was to use immunohistochemical (IHC) localization to identify ovarian dopaminergic and adrenergic nerves. Ovaries were collected during anestrus (n=9) and cyclicity (n=11). Tissue was prepared for IHC using antibodies specific to tyrosine hydroxylase (TH) and dopamine beta hydroxylase (DβH). Microscopic evaluation was performed, comparing the numbers and distribution of TH– versus DβH–specific immunoreactive (IR) neurons. Catecholaminergic neurons were present in all ovaries. The preponderance (P<0.0001) of IR neurons were dopaminergic. Neurons were moderately dispersed throughout the ovarian medulla and lightly in the cortex. Moderate to heavy neuron density was also noted around blood vessels. Neither dopaminergic nor adrenergic neuron type was consistently associated with specific reproductive structures. These results indicate that catecholaminergic innervation does exist in the equine ovary. The presence of ovarian DA nerves supports our hypothesis that DA has a direct role in ovarian function in the equine, although the mechanism of this function requires further study.

An overview of the noradrenergic system, including the identification of norepinephrine (NE) in animal tissue, its synthesis and metabolism, adrenoceptor classification, peripheral and central actions, uptake and storage, and mechanisms of NE release are presented. After characterizing the kinetic, ion dependence and inhibitor sensitivity of the norepinephrine transporter (NET) expressed in a recombinant cell line (LLC-NET cells), the influence of catecholamine (CA) metabolizing enzymes on studies of transport was assessed. Inhibitors of catechol-O-methyltransferase (COMT) potentiated the apparent uptake and retention of [3H]NE and [3H]DA. COMT inhibition had a greater influence on [3H]DA than [3H]NE uptake and retention, which corresponds to the higher spontaneous loss of radiolabel from cells exposed to [3H]DA than [3H]NE ([3H]methoxytyramine, is more lipophilic than [3H]normetanephrine). The monoamine oxidase inhibitor, pargyline, had no augmentary action on [3H]CA uptake, but actually inhibited substrate influx by blocking the NET. [3H]substrate specific differences were demonstrated for [3H]NE, [3H]DA and [3H]MPP+. For a given length of exposure to low Na+ or tyramine, [3H]NE release was the lowest, but most sensitive to NET inhibitors. Disparities in the kinetics of each [3H]substrate for the inwardly facing NET may account for this. Inhibitors of the NET were found to stimulate the efflux of [3H]substrates from preloaded cells incubated in a physiological HEPES buffer. Efflux was NET-dependent and differed greatly for each [3H]substrate. Inhibitor-induced release was greatest for [3H]MPP+ and least for [3H]NE. Finally, a functional model of carrier-mediated NE release in myocardial ischemia, was developed in this study. Release of [3H]MPP+ was stimulated by Na+-H+ exchanger (NHE) activation and modulated by inhibitors of the NET, NHE, Na+,K+-ATPase, and via a receptor-operated pathway. Excessive NE release contributes to severe myocardial arrhythmias, therefore an improved understanding of the carrier-mediated NE release process will ultimately enhance our ability to intervene and prevent the deleterious effects of excessive NE release.

No description available.