TOLERANCE TO DRUGS: MUCOUS GLAND CELL FUNCTION

药物耐受性：粘液腺细胞功能

• 批准号: 3211127
• 负责人: Jerry M. Farley
• 金额: $ 10.81万
• 依托单位: UNIVERSITY OF MISSISSIPPI MED CTR
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-03-01 至 1991-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3211127
• 关键词: adrenergic agents; adrenergic receptor; central nervous system stimulants; cocaine; density gradient ultracentrifugation; drug tolerance; electrical measurement; inhalation drug abuse; ion transport; local anesthetics; mucus; muscarinic receptor; oral mucosa; secretion; swine; weanling animal

The long term objective of this application is to gain a good understanding of the physiology and pharmacology of the function of mucus and fluid secretion in airways both in normal and disease states. Cocaine is a major drug of abuse which is taken primarily by inhalation of cocaine powder through the nose or by smoking the free-base. This means that the mucosal tissue of the nose and upper airways will be acutely exposed to high concentrations of this agent. Thus this drug either as a local anesthetic or as a sympathomimetic agent will lead to changes in the function of the submuscosal gland cells. In addition cocaine is generally taken repeatedly by those who use it. Thus, it may be that those who take it over an extended period of time may become tolerant to its action. This proposal is designed to determine the normal stimuli which induce the secretion of fluid and mucus from submuscosal gland cells. Then with this knowledge to determine what the acute and chronic effects of cocaine are on the functioning submuscosal gland cells. the properties of submuscosal gland cells isolated from weanling swine will be determined by isolating the cells from the mucosa using enzymes, followed by a purification step using density grandients. The cells will then be used in radioligand binding assays to determine the characteristics of the adrenergic and muscarinic receptors present on these cells and how these characteristics may be changed by cocaine exposure. Second the physiological function of the cells will be assayed by measuring neurotransmitter and neurally evoked mucus secretion adn chloride flux. The effect of cocaine on these functions will be determined. Finally, the effects of cocaine on the properties of ion channels in the tissue will be determined by use of the patch clamp technique. The ability of cocaine to block, or interact in other ways, with the ionic channels will be determined. The effects of chronic exposure of swine to cocaine on the function of submucosal gland cells will also be determined. Swine will be exposed via intranasal application of cocaine powder 2-3 times daily for up to 7 days. The pharmacological and physiological characteristics of gland cell function will then be determined by the methods given above. The effects of chronic cocaine exposure on submucosal gland cell function will also be examined in swine pretreated with reserpine to deplete peripheral catecholamine stores. This will permit an examination of the action of cocaine in the absence of its' sympathomimetic action.

该应用程序的长期目标是获得良好的