Karelson E, Laasik J, Sillard R
Institute of Biochemistry, Tartu University, Estonia.
Neuropeptides. 1995 Jan;28(1):21-8. doi: 10.1016/0143-4179(95)90070-5.
This study characterizes regional regulation of adenylate cyclase by galanin, neuropeptide Y (NPY), secretin and vasoactive intestinal peptide (VIP) in rat brain frontal cortex, hypothalamus and hippocampus. In our experimental system, galanin caused small detectable activation (10-20%) of basal adenylate cyclase activity in frontal cortex and hippocampus but had no effect on basal adenylate cyclase activity in hypothalamus. Galanin inhibited forskolin-stimulated adenylate cyclase in all three brain regions-hypothalamus, hippocampus and frontal cortex by 54.5%, 44.3% and 25.7%, respectively. NPY reduced basal and forskolin-stimulated enzyme activities by 35% only in frontal cortex, but not in the other two brain areas. Secretin had no effect in frontal cortex but caused similar adenylate cyclase activation in hypothalamus and hippocampus. VIP had a stimulatory effect of 32.8% and 32.4% in frontal cortex and hippocampus, respectively. The results indicate regional differences in adenylate cyclase modulation by the four peptides and reveal interesting relations in comparison with peptide and receptor densities in the three investigated brain regions.
本研究描述了甘丙肽、神经肽Y（NPY）、促胰液素和血管活性肠肽（VIP）对大鼠脑额叶皮质、下丘脑和海马中腺苷酸环化酶的区域调节作用。在我们的实验系统中，甘丙肽使额叶皮质和海马中的基础腺苷酸环化酶活性出现小幅度但可检测到的激活（10%-20%），但对下丘脑中的基础腺苷酸环化酶活性没有影响。甘丙肽分别抑制了下丘脑、海马和额叶皮质中福斯高林刺激的腺苷酸环化酶活性，抑制率分别为54.5%、44.3%和25.7%。NPY仅使额叶皮质中的基础和福斯高林刺激的酶活性降低35%，而在其他两个脑区则没有影响。促胰液素对额叶皮质没有影响，但在下丘脑和海马中引起类似的腺苷酸环化酶激活。VIP在额叶皮质和海马中的刺激作用分别为32.8%和32.4%。结果表明这四种肽对腺苷酸环化酶的调节存在区域差异，并揭示了与三个被研究脑区中肽和受体密度相比的有趣关系。
