Human angiotensin-converting enzyme (ACE) is a key enzyme in the regulation of blood pressure via the renin-angiotensin and kallikrein-kinin systems. A number of orally active drugs have been developed over the years that target somatic ACE, for the treatment of hypertension, myocardial infarction and congestive heart failure. Protein structural information about ACE is an important key for the understanding of the mechanism and substrate-specificity of the enzyme. However, this information has only begun to be elucidated in the past year, with the solution of crystal structures of human testis ACE (tACE), and homologues Drosophila AnCE and human ACE2. tACE is identical to the C-terminal domain of somatic ACE, which consists of two homologous domains, each having a slightly different substrate-specificity. This thesis describes the purification, crystallisation and X-ray crystal structure-determination of a glycosylation-deficient mutant of tACE, tACEG1,3, to 2.9 &Aring / .

Thesis (Ph. D.)--University of Missouri--Columbia, 1996. / "December 1996" Typescript. Vita. Includes bibliographical references (l. 121-128). Also available on the Internet.

Thesis (Ph.D.) - University of Queensland, 2003. / Includes bibliography.

Magister Scientiae - MSc / Human angiotensin-converting enzyme (ACE) is a key enzyme in the regulation of blood pressure via the renin-angiotensin and kallikrein-kinin systems. A number of orally active drugs have been developed over the years that target somatic ACE, for the treatment of hypertension, myocardial infarction and congestive heart failure. Protein structural information about ACE is an important key for the understanding of the mechanism and substrate-specificity of the enzyme. However, this information has only begun to be elucidated in the past year, with the solution of crystal structures of human testis ACE (tACE), and homologues Drosophila AnCE and human ACE2. tACE is identical to the C-terminal domain of somatic ACE, which consists of two homologous domains, each having a slightly different substrate-specificity. This thesis describes the purification, crystallisation and X-ray crystal structure-determination of a glycosylation-deficient mutant of tACE, tACEG1,3, to 2.9 Å. The structure of tACE-G1,3 aligns closely with that of native tACE, indicating that the mutations did not alter the conformation. The ability to achieve minimal glycosylation of tACE for crystallisation purposes via mutation, rather than using expensive glycosidase inhibitors, iii should prove advantageous for further structural studies, such as the study of the binding of novel inhibitors. In all of the tACE structures thus far observed, the active site is closed off from the external medium in a deep cleft, so that it is unclear how a large substrate molecule could gain access. However, a hinge motion that opens this cleft has been observed in the structures of ACE2. Temperature factor and sequence comparison between tACE, tACE-G1,3, AnCE and ACE2 suggests the functional conservation of three flexible loop regions, as well as the sequence conservation of three constrained regions, involved in the hinge. Normal mode analysis reveals the intrinsic flexibility of tACE, and further suggests that a putative open form of tACE would behave similarly to the open form of ACE2. Based on these indications, a conservation of the ACE2 hinge-bending mechanism is proposed. Temperature factor analysis also reveals that subdomain II, containing bound chloride ions, is more structurally rigid than subdomain I, in all structures considered. Based on these results, lines of investigation are suggested that should yield insight into the mechanisms of action of ACE and its association with various substrates and inhibitors, ideally aiding in the development of novel drugs for the treatment of cardiac disease. / South Africa

No description available.

A research report submitted to the Faculty of Health Sciences, University of Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science (MSc) in Pharmaceutical Affairs. / Lack of information has been identified as a major factor as to why patients do not take their medicines as the prescriber intends. Provision of appropriate information in a suitable form is therefore crucial. The package insert (PI) is the document that ensures the safe and effective use of the medicine under most circumstances. It presents a scientific, objective account of the medicine’s use as established by pre-clinical, clinical and often post-marketing studies. The patient information leaflet (PIL), which contains information for the consumer should be less scientific. South African legislation states that information contained in PILs must be aligned to PIs but the text must be readily intelligible for the patient. The study included a detailed comparison of prescribing information contained in the PI compared to the PIL in selected Angiotensin Receptor Blockers (ARBs). Findings of this comparative analysis revealed that key safety information was omitted from the PILs. An evaluation of the readability of the PILs was also performed by the use of Fry’s readability formula as well as applying elements of critical discourse analysis to determine if the texts in the PILs are suitable for its purpose. The results of the Fry’s readability assessments of all the PILs indicated that they had exceeded the recommended grade 7 reading level, which is in line with the adult literacy rate that qualifies anyone older than 15 years with a grade 7 qualification as being literate. Findings from the critical discourse analysis of the PILs show frequent use of medical jargon, complex sentence construction as well as ambiguity and slippage in the meaning of the texts in the PILs. The texts are not patient-friendly. Overall, the findings from this study indicate an urgent need to address the poor construction of PILs, to ensure that patients receive appropriate written prescribing information. This will ultimately ensure the safe and effective use of the medicine. / KP2020

Siu-Yin Sylvia Lam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 123-140). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iv / 英中譯名對照 --- p.vi / Acknowledgements --- p.vii / Table of Contents --- p.viii / Abbreviations --- p.xiii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Overview of Carotid Body --- p.1 / Chapter 1.1.1 --- Type I Cells --- p.3 / Chapter 1.1.2 --- Type II Cells --- p.4 / Chapter 1.1.3 --- Blood Vessels --- p.5 / Chapter 1.1.4 --- Innervation --- p.5 / Chapter 1.1.5 --- Biochemistry --- p.6 / Chapter 1.1.6 --- Physiology and Function --- p.7 / Chapter 1.2 --- The Renin-Angiotensin System (RAS) --- p.8 / Chapter 1.2.1 --- Circulating RAS --- p.8 / Chapter 1.2.1.1 --- Angiotensinogen --- p.10 / Chapter 1.2.1.2 --- Renin --- p.10 / Chapter 1.2.1.3 --- Angiotensin I --- p.11 / Chapter 1.2.1.4 --- Angiotensin Converting Enzyme --- p.12 / Chapter 1.2.1.5 --- Angiotensin II --- p.12 / Chapter 1.2.1.6 --- Angiotensin II Receptors --- p.13 / Chapter 1.2.1.7 --- Angiotensin IV and Angiotensin IV Receptor --- p.15 / Chapter 1.2.2 --- Tissue RAS --- p.16 / Chapter 1.3 --- Hypoxia and Carotid Body --- p.18 / Chapter 1.4 --- Hypoxia and RAS --- p.21 / Chapter 1.5 --- Hypoxia and RAS in Carotid Body --- p.23 / Chapter 1.6 --- Aims of Study --- p.24 / Chapter 1.6.1 --- Existence of Functional Angiotensin II Receptors --- p.24 / Chapter 1.6.2 --- Regulation and Function of Angiotensin II Receptors by Chronic Hypoxia --- p.24 / Chapter 1.6.3 --- Existence of an Intrinsic Angiotensin-generating System --- p.25 / Chapter 1.6.4 --- Regulation of Local RAS by Chronic Hypoxia --- p.25 / Chapter 1.6.5 --- Studies of AT4 Receptor --- p.26 / Chapter Chapter 2 --- Materials and Methods / Chapter 2.1 --- Experimental Animals and Rat Models --- p.27 / Chapter 2.1.1 --- Rat Model of Chronic Hypoxia --- p.27 / Chapter 2.1.2 --- Isolation of Carotid Body --- p.28 / Chapter 2.2 --- Semi-quantitative Reverse Transcriptase-polymerase Chain Reaction (RT-PCR) --- p.30 / Chapter 2.2.1 --- Total RNA Extraction and Quantification --- p.30 / Chapter 2.2.2 --- Reverse Transcription (RT) --- p.31 / Chapter 2.2.3 --- Polymerase Chain Reaction (PCR) --- p.31 / Chapter 2.2.4 --- Gel Electrophoresis --- p.34 / Chapter 2.2.5 --- Optimization of Semi-quantitative RT-PCR for RAS Gene Analysis --- p.34 / Chapter 2.3 --- Northern Blotting --- p.35 / Chapter 2.3.1 --- Transfer of Denatured RNA to Nitrocellulose Membrane By Capillary Elution --- p.35 / Chapter 2.3.2 --- Hybridization --- p.36 / Chapter 2.4 --- In-situ Hybridization --- p.38 / Chapter 2.4.1 --- Linearization of Angiotensinogen cDNA --- p.38 / Chapter 2.4.2 --- Riboprobe Preparation --- p.38 / Chapter 2.4.3 --- Quantification and Gel Electrophoresis of Riboprobes --- p.39 / Chapter 2.4.4 --- In-situ Hybridization Histochemistry --- p.39 / Chapter 2.5 --- Immunohistochemistry --- p.42 / Chapter 2.5.1 --- Preparation of Cryosection --- p.42 / Chapter 2.5.2 --- Indirect Immunoperoxidase Staining --- p.42 / Chapter 2.5.3 --- Immunofluorescent Double Staining --- p.43 / Chapter 2.6 --- Western Blot Analysis --- p.45 / Chapter 2.6.1 --- Preparation of Angiotensinogen Protein --- p.45 / Chapter 2.6.2 --- Quantification of Protein Concentration --- p.45 / Chapter 2.6.3 --- Sample Preparation --- p.45 / Chapter 2.6.4 --- Sodium Dodecyl-sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.46 / Chapter 2.6.5 --- Electroblotting and Immunodetection of Proteins --- p.46 / Chapter 2.7 --- Spectrofluorimetric Measurement and In-vitro Electrophysiology --- p.48 / Chapter 2.7.1 --- Dissociation of Carotid Body Type I Cells and Spectrofluorimetric Measurement --- p.48 / Chapter 2.7.2 --- In-vitro Electrophysiology --- p.49 / Chapter 2.8 --- Assay of ACE Activity --- p.51 / Chapter 2.8.1 --- Crude Membrane Preparation --- p.51 / Chapter 2.8.2 --- Basic Principle for ACE Activity Measurement --- p.51 / Chapter 2.8.3 --- Measurement of ACE Activity --- p.51 / Chapter 2.8.4 --- Fluorescence Measurement --- p.53 / Chapter 2.9 --- In-vitro Autoradiography and Fluorescence-labeled Binding Assay for Angiotensin IV --- p.54 / Chapter 2.9.1 --- Preparation of Frozen Tissue Sections --- p.54 / Chapter 2.9.2 --- Localization and Density of AT4 Receptor --- p.54 / Chapter 2.10 --- Statistics and Data Analysis --- p.57 / Chapter Chapter 3 --- Results / Chapter 3.1 --- Functional Expression of Angiotensin II Receptors --- p.58 / Chapter 3.1.1 --- [Ca2+]i Response to Angiotensin II --- p.58 / Chapter 3.1.2 --- Antagonistic Blockade of Angiotensin II Receptor Subtypes --- p.58 / Chapter 3.1.3 --- Expression of AT1 Receptors mRNA --- p.61 / Chapter 3.1.4 --- Cellular Localization of AT1 Receptors Protein --- p.61 / Chapter 3.2 --- Effect of Chronic Hypoxia on the Expression and Function of Angiotensin II Receptors --- p.64 / Chapter 3.2.1 --- Effect of Chronic Hypoxia on the Expression of AT1 Receptors --- p.64 / Chapter 3.2.2 --- Effect of Chronic Hypoxia on the Expression of AT2 Receptors --- p.67 / Chapter 3.2.3 --- Cellular Localization of the AT1 Receptor by Chronic Hypoxia --- p.69 / Chapter 3.2.4 --- Increase of Afferent Nerve Activities of the Carotid Body In-vitro by Angiotensin II --- p.71 / Chapter 3.2.5 --- Inhibition of Angiotensin II-mediated Response in Chronically Hypoxic Carotid Body by Losartan --- p.73 / Chapter 3.3 --- Evidence for the Existence of an Intrinsic Angiotensin-generating System --- p.75 / Chapter 3.3.1 --- Expression and Localization of Angiotensinogen mRNA --- p.75 / Chapter 3.3.2 --- Expression and Localization of Angiotensinogen Protein --- p.78 / Chapter 3.3.3 --- Expression of Renin mRNA --- p.81 / Chapter 3.3.4 --- Expression of ACE mRNA --- p.81 / Chapter 3.4 --- Effect of Chronic Hypoxia on the Locally-generated Angiotensin System --- p.85 / Chapter 3.4.1 --- Effect of Chronic Hypoxia on the Expression of Angiotensinogen mRNA --- p.85 / Chapter 3.4.2 --- Effect of Chronic Hypoxia on the Localization of Angiotensinogen mRNA --- p.87 / Chapter 3.4.3 --- Effect of Chronic Hypoxia on the Expression of Angiotensinogen Protein --- p.89 / Chapter 3.4.4 --- Effect of Chronic Hypoxia on the Expression of ACE --- p.91 / Chapter 3.5 --- Time-course Effect of Chronic Hypoxia on ACE Activity --- p.93 / Chapter 3.6 --- Preliminary Studies of AT4 Receptor --- p.98 / Chapter 3.6.1 --- In-vitro Autoradiographic Study of AT4 Receptors --- p.98 / Chapter 3.6.2 --- Localization of AT4 Receptors --- p.100 / Chapter Chapter 4 --- Discussion / Chapter 4.1 --- Functional Expression of Angiotensin II Receptors --- p.102 / Chapter 4.2 --- Upregulation and Function of Angiotensin II Receptors --- p.105 / Chapter 4.3 --- Existence of a Local RAS --- p.108 / Chapter 4.4 --- Regulation of the Local RAS --- p.112 / Chapter 4.5 --- Time-dependent Changes of ACE Activity --- p.155 / Chapter 4.6 --- Presence and Regulation of AT4 Receptor --- p.117 / Chapter 4.7 --- Conclusion --- p.120 / Chapter 4.8 --- Future Works --- p.121 / Chapter Chapter 5 --- References --- p.123

by Pui-fan Wong. / "December 2001." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Abstract not available

Diss. (sammanfattning) Uppsala : Univ., 2002. / Härtill 4 uppsatser.