Huang Y T, Lin H C, Yu P C, Lee F Y, Tsai Y T, Lee S D, Yang M C
Institute of Traditional Medicine, School of Medicine, National Yang-Ming University, Taiwan.
J Hepatol. 1996 Feb;24(2):194-9. doi: 10.1016/s0168-8278(96)80029-8.
BACKGROUND/AIMS: Vascular hyporesponsiveness in portal hypertension is well documented in the arterial tissue. The present study aimed to investigate the possible changes in the portal vein from portal hypertensive rats.
Portal hypertension was induced by partial portal vein ligation. Fourteen days after surgery, portal veins were removed for contractile study and measurement of cAMP, cGMP and [Ca2+]i.
In vitro tension preparation showed a decreased maximum response to norepinephrine in portal vein of portal vein ligated rats (38.3 +/- 4.1 vs. 23.4 +/- 1.5 mN/mm2). The pA2 values of WB4101 and yohimbine (alpha1- and alpha2-adrenoceptor antagonist, respectively) were not different between the two groups. Tissue cAMP (14.4 +/- 0.9 vs. 12.2 +/- 0.7 pmol/mg protein), but not cGMP, content was increased and intracellular calcium [Ca2+]i levels (247 +/- 9 vs. 281 +/- 13 nM) were decreased in portal vein ligated rats.
These results showed that in portal vein from portal vein ligated rats, vascular hyporesponsiveness and an increase in basal cAMP content and a decrease in basal [Ca2+]i were observed.
背景/目的：门静脉高压时动脉组织中的血管低反应性已有充分记录。本研究旨在调查门静脉高压大鼠门静脉可能发生的变化。
通过部分门静脉结扎诱导门静脉高压。术后14天，取出门静脉进行收缩研究以及环磷酸腺苷（cAMP）、环磷酸鸟苷（cGMP）和细胞内钙离子浓度（[Ca2+]i）的测量。
体外张力实验显示，门静脉结扎大鼠门静脉对去甲肾上腺素的最大反应降低（38.3±4.1对23.4±1.5 mN/mm2）。两组间WB4101和育亨宾（分别为α1 - 和α2 - 肾上腺素能受体拮抗剂）的pA2值无差异。门静脉结扎大鼠的组织cAMP含量增加（14.4±0.9对12.2±0.7 pmol/mg蛋白），而cGMP含量未增加，且细胞内钙离子[Ca2+]i水平降低（247±9对281±13 nM）。
这些结果表明，在门静脉结扎大鼠的门静脉中，观察到血管低反应性、基础cAMP含量增加以及基础[Ca2+]i降低。
