YOGO Takuya, KANEDA Takeharu, NEZU Yoshinori, HARADA Yasuji, HARA Yasushi, TAGAWA Masahiro, URAKAWA Norimoto, SHIMIZU Kazumasa
Laboratory of Veterinary Surgery, Nippon Veterinary and Life Science University, Musashino, Tokyo, Japan.
J Vet Med Sci. 2009 Nov;71(11):1449-53. doi: 10.1292/jvms.001449.
The effects of various selective phosphodiesterase (PDE) inhibitors on muscle contractility and cyclic nucleotide contents in porcine iris sphincter were investigated. Forskolin and sodium nitroprusside inhibited carbachol (CCh)-induced contraction in a concentration-dependent manner. Various selective PDE inhibitors, vinpocetine (type 1), erythro -9-(2-hydroxy-3-nonyl)adenine (EHNA, type 2), milrinone (type 3), Ro20-1724 (type 4) and zaprinast (type 5), also inhibited CCh-induced contraction in a concentration-dependent manner. The rank order of potency of IC(50) was zaprinast > Ro20-1724 > EHNA >/= milrinone > vinpocetine. In the presence of CCh (0.3 muM), vinpocetine, milrinone and Ro20-1724 increased cAMP, but not cGMP, contents. In contrast, zaprinast and EHNA both increased cGMP, but not cAMP, contents. This indicates that vinpocetine-, milrinone- and Ro20-1724-induced relaxation is correlated with cAMP, while EHNA- and zaprinast- induced relaxation is correlated with cGMP in porcine iris sphincter.
研究了各种选择性磷酸二酯酶（PDE）抑制剂对猪虹膜括约肌肌肉收缩性和环核苷酸含量的影响。福斯可林和硝普钠以浓度依赖性方式抑制卡巴胆碱（CCh）诱导的收缩。各种选择性PDE抑制剂，长春西汀（1型）、赤藓红-9-（2-羟基-3-壬基）腺嘌呤（EHNA，2型）、米力农（3型）、Ro20-1724（4型）和扎普司特（5型），也以浓度依赖性方式抑制CCh诱导的收缩。IC（50）效力的顺序为扎普司特>Ro20-1724>EHNA≥米力农>长春西汀。在存在CCh（0.3μM）的情况下，长春西汀、米力农和Ro20-1724增加了cAMP含量，但未增加cGMP含量。相反，扎普司特和EHNA均增加了cGMP含量，但未增加cAMP含量。这表明在猪虹膜括约肌中，长春西汀、米力农和Ro20-1724诱导的舒张与cAMP相关，而EHNA和扎普司特诱导的舒张与cGMP相关。
