Yu O, Ouyang A
Division of Gastroenterology, Hospital of the University of Pennsylvania, Philadelphia 19104, USA.
Dig Dis Sci. 1997 Jun;42(6):1146-53. doi: 10.1023/a:1018877318101.
The effects of aging and diabetes on the distribution of beta-adrenoceptor subtypes in the gut were investigated in the BB rat. [125I]Cyanopindolol binding to 10-micron sections was evaluated using film autoradiography. Cyanopindolol binding to beta-, beta 1-, and beta 2-adrenoceptors was displaced by 1 microM propranolol, 50 nM ICI-89-406, and 100 nM ICI-118-551, respectively. beta-Adrenoceptor binding was highest in the circular muscle of proximal colon and lowest in the pylorus of 4- to 5-month-old rats. Aging (8- to 10-month-old vs. 4- to 5-month-old rats) was associated with increased beta-adrenoceptor binding in the pylorus and reduced binding in the proximal colon. Diabetes had a time-dependent effect on the level of beta-adrenoceptor binding. It was increased in the antral and pyloric stomach but longer periods of diabetes caused a reduction in beta-adrenoceptor binding in the pylorus. Those in the intestine were reduced time-dependently and involved beta 1- or beta 2-adrenoceptors or both.
在BB大鼠中研究了衰老和糖尿病对肠道β-肾上腺素能受体亚型分布的影响。使用胶片放射自显影法评估[125I]氰吲哚洛尔与10微米切片的结合情况。氰吲哚洛尔与β-、β1-和β2-肾上腺素能受体的结合分别被1微摩尔普萘洛尔、50纳摩尔ICI-89-406和100纳摩尔ICI-118-551取代。在4至5月龄大鼠中，β-肾上腺素能受体结合在近端结肠环行肌中最高而在幽门中最低。衰老（8至10月龄大鼠与4至5月龄大鼠相比）与幽门中β-肾上腺素能受体结合增加及近端结肠中结合减少有关。糖尿病对β-肾上腺素能受体结合水平有时间依赖性影响。在胃窦和幽门中其增加，但糖尿病时间延长会导致幽门中β-肾上腺素能受体结合减少。肠道中的β-肾上腺素能受体结合随时间减少，涉及β1-或β2-肾上腺素能受体或两者。
