Gayanne O'Neil

Learn More
Major depression disorder is a common psychiatric disease with a major economic impact on society. In many cases, no effective treatment is available. The etiology of major depression is complex, but it is clear that the disease is, to a large extent, determined genetically, especially among individuals with a familial history of major depression,(More)
Patency rates of bypass graft conduits are thought to be influenced by the determinants of vascular tone. This study has comparatively examined the response of the human internal mammary and gastroepiploic arteries to potassium, noradrenaline, dopamine, 5-hydroxytryptamine, thromboxane, and histamine. The response to potassium was significantly greater in(More)
Immunochemical studies were carried out on the ascidian Ciona intestinalis to determine the character and distribution of the tachykinins neurokinin A (NKA) and substance P (SP). Antisera specific for the C-terminus of mammalian SP, and for the N-terminus of mammalian SP and NKA, were used to monitor tissue extracts from Ciona. Parallel immunocytochemical(More)
Endothelium-dependent relaxations in response to substance P and bradykinin were lower in atherosclerotic than in normal human coronary arteries. The relaxation induced by substance P was inhibited by L-NG-monomethylarginine (L-NMMA), which shows that release of nitric oxide is involved in the mediation of endothelium-dependent relaxation in these arteries.(More)
OBJECTIVE It has been hypothesised that compromised endothelial function can contribute to the toxic manifestations associated with cyclosporin therapy. In vitro animal studies have implicated inhibition of release of the endothelium derived relaxing factor, nitric oxide; however, this has not been investigated in human tissue. The present study(More)
OBJECTIVE The aim was to examine the capacity of the human saphenous vein (native and surgically prepared) and the internal mammary artery to generate cyclic GMP, the second messenger that mediates smooth muscle relaxation following production of nitric oxide. METHODS 209 vessel segments were used from 22 patients undergoing coronary revascularisation.(More)
The human gastroepiploic artery has been used as a coronary artery bypass conduit in a limited number of clinical studies. It has been postulated that the capacity of the endothelium to release vasoactive substances may contribute to differing patency rates observed in established bypass grafts. We have now examined endothelial function in the human(More)
The inferior epigastric artery is a putative arterial bypass graft. The receptor mechanisms that control vascular tone are thought to play a role in the performance of bypass conduits. We have compared the vascular reactivity of the inferior epigastric artery with that of the internal mammary artery. Segments from a total of 15 inferior epigastric and 12(More)