Effects of acidic fibroblast growth factor released by feeding on learning and memory, endocrine and immune systems

1. aFGF及其片段对学习和记忆的影响：众所周知，快速老化小鼠（SAMP 8）具有恶化的学习和记忆能力。在本研究中，SAMP 8接受皮下注射注射aFGF或其片段。在21日龄断奶后开始注射，每周重复一次，持续10个月。结果表明，aFGF或其片段能显著提高SAMP 8的被动回避和Morris水迷宫学习记忆能力。aFGF及其片段对SAMP 8学习记忆功能的有益作用可能与保护内侧隔胆碱能神经元的功能有关. aFGF对内分泌系统的影响：大鼠i. c. v.注射aFGF可显著升高血浆皮质酮和肾上腺素水平。在aFGF注射之前预先I. c. v.注射抗CRF抗体消除了血浆皮质酮和肾上腺素水平的增加。因此，可以说aFGF通过CRF激活下丘脑-垂体-肾上腺皮质轴和肾上腺髓质分泌。aFGF及其片段对免疫系统的影响：采用流式细胞术观察aFGF及其片段对大鼠腹腔巨噬细胞吞噬功能的影响。结果表明，aFGF、aFGF（1-20）和aFGF（1-29）剂量依赖性地激活巨噬细胞的吞噬作用。

1. Effect of aFGF and its fragment on learning and memory : It is well known that senescence-accelerated mice (SAMP8) have a deteriorated ability on learning and memory. In the present study, SAMP8 received s.c. injections of aFGF or its fragment. The injections were started after weaning at 21 days of age and repeated once a week for 10 months. Consequently, aFGF or its fragment significantly improved the ability on learning and memory of SAMP8, when examined with passive avoidance test and Morris water maze test. The beneficial effect of aFGF and its fragment on learning and memory function in SAMP8 may be related to a preservation of function in medial septum cholinergic neurons.2. Effect of aFGF on endocrine system : I.c.v. injections of aFGF in rats significantly increased plasma corticosterone level and plasma adrenaline level. Pre-I.c.v. injections of anti-CRF antibody before aFGF injections abolished the increase of plasma corticosterone and adrenaline levels. Thus, it may be possible to state that aFGF activates hypotlhlamic-pituitary-adrenocortical axis and adrenomedullary secretion through CRF.3. Effect of aFGF and its fragments on immune system : Action of aFGF and its fragments on phagocytosis of peritoneal macrophages in rats was investigated by flow cytometry. The results indicate that aFGF, aFGF(1-20) and aFGF(1-29) dose-dependently activate phagocytosis of macrophages.