頁籤選單縮合
題名 | Cardiovascular Effects of Microinjection of Angiotensin Ⅲ in Rat Brainstem Nuclei=微量注射丙型血管張力素至大白鼠腦幹神經核所產生之心臟血管作用 |
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作 者 | 林惠卿; 葛魯蘋; 曾清俊; | 書刊名 | 醫學研究 |
卷期 | 15:4 1995.01[民84.01] |
頁次 | 頁245-256 |
分類號 | 418.2135 |
關鍵詞 | 丙型血管張力素; 腦幹核; 孤立束核; 最後區; Angiotensin Ⅲ; Brainstem nuclei; Nucleus tractus solitarii; Area postrema; |
語文 | 英文(English) |
中文摘要 | 丙型血管張力素(AIII)被認為是與乙型血管張力素(AII)相同強度之神經胜肽。在本研究中,我們探討了微量注射AIII至S-D大白鼠之孤立束核及最後區所產生的心臟血管作用。當低劑量的AIII微量注射到孤立束核及最後區後可見劑量依賴性的降壓及降心跳作用,而最大的降壓作用在9.6 pmol時產生。當劑量增力時,則見到升壓及心跳加快之作用。在降壓及升壓的同時,我們亦同時記錄到腎臟神經活性的抑制現象。上述之心臟血管作用可被預先處理之AIII選擇性抑制劑所全部或部份抑制。本研究之結果顯示急性的興奮孤立束核及最後區之血管張力素接受器本質上會產生降壓作用,同時此心臟血管作用主要是經由抑制交感神經活性而得。 |
英文摘要 | Angiotensin III (AIII) has been reported to be an equipotent neuropeptide similar to angiotensin II (AII). In this study, we investigated the cardiovascular effects of microinjection of AIII into the nucleus tractus solitarii (NTS) and area postrema (AP) of male Sprague-Dawley rats. When low doses of AIII were microinjected into either NTS or AP, a dose-dependent depressor and bradycardic effect were observed, the maximal depressor effect occurring at 9.6 pmol. As the doses of AIII microinjected into the NTS increased, pressor and tachycardic effect were observed. The sympathetic nerve activity was inhibited in both pressor and depressor conditions. The cardiovascular effects of AIII can be partially or completely abolished after pretreatment of selective antagonists. These results may suggest that acute activation of the AIII receptors in the NTS and AP is depressor in nature and this cardiovascular effects might be through inhibition of sympathetic nerve activity. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。