Levine J H, Leaming A B
Endocr Res Commun. 1977;4(6):329-41. doi: 10.3109/07435807709073626.
The role of cyclic AMP in the regulation of hepatic ornithine decarboxylase (ODC) activity in the rat was studied in the whole animal and in the perfused organ. Dibutyryl cyclic AMP or butyrate given to intact rats increased ODC activity; this increase was abolished by hypophysectomy 1 h prior to administering ether compound. Administration of 1 mg 1-methyl-3-isobutylxanthine (MIX) to intact rats increased ODC activity within 4 hours whereas hypophysectomy 1 h before treatment prevented this increase. No change in hepatic cyclic AMP content was seen in either intact or hypophysectomized rats following MIX. Perfusion with 0.5 mM dibutyryl cyclic AMP decreased ODC activity in isolated livers whereas perfusion with 0.5 mM 8-bromocyclic GMP produced a small increase in ODC activity. These data suggest that the effect of dibutyryl cyclic AMP in intact animals may be a property of the butyrate and that this action as well as the action of MIX may be mediated through the permissive effect of pituitary and/or adrenal hormones. The normal hepatocyte does not increase its ornithine decarboxylase activity after direct exposure to dibutyryl cyclic AMP.
在整体动物和灌注器官中研究了环磷酸腺苷（cAMP）在调节大鼠肝脏鸟氨酸脱羧酶（ODC）活性中的作用。给完整大鼠注射二丁酰环磷酸腺苷或丁酸盐可增加ODC活性；在给予醚类化合物前1小时进行垂体切除可消除这种增加。给完整大鼠注射1毫克1-甲基-3-异丁基黄嘌呤（MIX）在4小时内可增加ODC活性，而在治疗前1小时进行垂体切除可阻止这种增加。MIX处理后，完整或垂体切除大鼠的肝脏环磷酸腺苷含量均未见变化。用0.5 mM二丁酰环磷酸腺苷灌注可降低离体肝脏中的ODC活性，而用0.5 mM 8-溴环磷酸鸟苷灌注可使ODC活性略有增加。这些数据表明，二丁酰环磷酸腺苷在完整动物中的作用可能是丁酸盐的特性，并且这种作用以及MIX的作用可能是通过垂体和/或肾上腺激素的允许作用介导的。正常肝细胞在直接暴露于二丁酰环磷酸腺苷后不会增加其鸟氨酸脱羧酶活性。
