Ishikawa Y, Chen C, Ishida H
Department of Pharmacology, Tokushima University School of Dentistry, Japan.
Res Exp Med (Berl). 1993;193(4):255-62. doi: 10.1007/BF02576233.
The purpose of this study was to investigate the effect of starvation on the cellular function of rat parotid glands in relation to the diurnal variation of amylase secretion from the tissue. Salivary amylase secreted from the glands of rats starved for 24 h showed diurnal variation, with two peaks at 13 and 21 h. The peak at 21 h was more notable than that in fed rats, because of the accumulation of a large amount of amylase in the tissue due to starvation. Maximal binding (Bmax) values of [3H]dihydroalprenolol in the parotid membrane of starved rats also showed diurnal variation, with marked peak at 13 and 21 h. However, phosphorylation of nuclear non-histone proteins in starved rat parotid glands showed diurnal variation, with peaks at 17 and 1 h. This phasing was delayed by 4 h in comparison to that of fed rats, suggesting that the delay of diurnal variation of amylase secretion commences at least a few days after the beginning of starvation. These results indicate that changes in salivary amylase secreted from parotid glands of rats starved for 24 h coupled with those in the number of beta-adrenoceptors in the tissue show the same diurnal variation as observed in fed rats. Starvation of rats for 24 h does not appear to influence the response of parotid gland cells to stimuli.
本研究的目的是探讨饥饿对大鼠腮腺细胞功能的影响，以及与该组织淀粉酶分泌的昼夜变化之间的关系。饥饿24小时的大鼠腮腺分泌的唾液淀粉酶呈现昼夜变化，在13时和21时出现两个峰值。由于饥饿导致组织中大量淀粉酶的积累，21时的峰值比喂食大鼠更为显著。饥饿大鼠腮腺膜中[3H]二氢阿普洛尔的最大结合（Bmax）值也呈现昼夜变化，在13时和21时出现明显峰值。然而，饥饿大鼠腮腺中核非组蛋白的磷酸化呈现昼夜变化，在17时和1时出现峰值。与喂食大鼠相比，这种相位延迟了4小时，这表明淀粉酶分泌昼夜变化的延迟至少在饥饿开始几天后就开始了。这些结果表明，饥饿24小时的大鼠腮腺分泌的唾液淀粉酶的变化以及组织中β-肾上腺素能受体数量的变化与喂食大鼠中观察到的昼夜变化相同。大鼠饥饿24小时似乎不会影响腮腺细胞对刺激的反应。
