Freetly H C, Ferrell C L
US Department of Agriculture, Roman L Hruska US Meat Animal Research Center, Clay Center, Nebraska 68933.
J Endocrinol. 1994 May;141(2):353-8. doi: 10.1677/joe.0.1410353.
The objective of this study was to determine whether circulating concentrations or prior exposure to estradiol-17 beta (OE2) and progesterone affected their uptake by splanchnic tissues. Catheters were surgically placed in the portal vein, a branch of the hepatic vein, a mesenteric vein and the abdominal aorta of three multiparous ovariectomized Dorset ewes. Blood and plasma flow across the portal-drained viscera (PDV) and the liver, and net uptake of OE2 and O2 consumption in these same tissues were determined in ovariectomized ewes (control), during OE2 infusion into the jugular vein, 7 days after an OE2 implant had been given, and during OE2 infusion into the jugular vein 7 days after an OE2 implant. The above treatments were repeated for progesterone. Plasma flows across visceral organs were determined by marker dilution (para-aminohippuric acid), and OE2 and progesterone concentrations were determined by radioimmunoassay. During the infusion with OE2, OE2 arterial concentration (mean +/- S.D.) was 346 +/- 199 pg/ml, PDV net uptake was 9.7 +/- 5.6 micrograms OE2/h and hepatic net uptake was 15.5 +/- 9.5 micrograms OE2/h. Hepatic uptake was 82% of the jugular OE2 infusion rate. Blood flow and oxygen consumption by hepatic tissue increased when ewes were exposed to an OE2 implant for 7 days. During the infusion with progesterone, progesterone arterial concentration (mean +/- S.D.) was 8.8 +/- 3.4 ng/ml, PDV net uptake was 220 +/- 118 micrograms progesterone/h and hepatic net uptake was 238 +/- 52 micrograms progesterone/h. Hepatic net uptake was 23% of the progesterone jugular infusion rate.
本研究的目的是确定循环浓度或先前暴露于雌二醇 - 17β（OE2）和孕酮是否会影响它们被内脏组织摄取。通过手术将导管插入三只经产去卵巢多塞特母羊的门静脉、肝静脉分支、肠系膜静脉和腹主动脉。测定去卵巢母羊（对照组）、颈静脉输注OE2期间、给予OE2植入物7天后以及给予OE2植入物7天后颈静脉输注OE2期间，流经门静脉引流内脏（PDV）和肝脏的血流和血浆流量，以及这些相同组织中OE2的净摄取量和氧气消耗量。对孕酮重复上述处理。通过标记稀释法（对氨基马尿酸）测定流经内脏器官的血浆流量，通过放射免疫测定法测定OE2和孕酮浓度。在输注OE2期间，OE2动脉浓度（平均值±标准差）为346±199 pg/ml，PDV净摄取量为9.7±5.6微克OE2/小时，肝脏净摄取量为15.5±9.5微克OE2/小时。肝脏摄取量为颈静脉OE2输注速率的82%。当母羊暴露于OE2植入物7天时，肝脏组织的血流和氧气消耗量增加。在输注孕酮期间，孕酮动脉浓度（平均值±标准差）为8.8±3.4 ng/ml，PDV净摄取量为220±118微克孕酮/小时，肝脏净摄取量为238±52微克孕酮/小时。肝脏净摄取量为孕酮颈静脉输注速率的23%。
