Sherwood O D, Crnekovic V E
Endocrinology. 1979 Apr;104(4):893-7. doi: 10.1210/endo-104-4-893.
Highly purified rat relaxin has been radioiodinated to specific activities of approximately 100 micro Ci/microgram with the Bolton and Hunter reagent [N-succinimidyl 3-(4-hydroxy-5-[125I]iodophenyl) propionate]. A rabbit antirat relaxin serum, applicable in a final dilution of 1:100,000, was developed in a rabbit using unconjugated highly purified rat relaxin. A specific and precise double antibody RIA for rat relaxin sufficiently sensitive to routinely measure from 32--2000 pg rat relaxin was developed. Using this RIA, relaxin immunoactivity levels in extracts of pregnant rat ovaries were found to rise from 0.8 microgram/geq ovarian fresh tissue on day 8 of pregnancy to 723 microgram/geq ovarian fresh tissue on day 20 of pregnancy and then to drop precipitously to 6 microgram/geq ovarian fresh tissue on day 1 of lactation. Consistent with the occurrence and relative levels of relaxin in the ovarian extracts, levels of relaxin in pregnant rat serum were less than 2 ng/ml on day 10 of pregnancy, approximately 150 ng/ml on days 20 and 22 of pregnancy, and 12 ng/ml on day 2 of lactation.
高纯度的大鼠松弛素已用博尔顿-亨特试剂[N-琥珀酰亚胺基3-(4-羟基-5-[125I]碘苯基)丙酸酯]进行放射性碘化，比活度约为100微居里/微克。用未结合的高纯度大鼠松弛素在兔体内制备了一种兔抗大鼠松弛素血清，最终稀释度可达1:100,000。开发了一种特异性强、精确的大鼠松弛素双抗体放射免疫分析法（RIA），其灵敏度足以常规检测32 - 2000皮克的大鼠松弛素。使用这种RIA，发现妊娠大鼠卵巢提取物中的松弛素免疫活性水平从妊娠第8天的0.8微克/克卵巢新鲜组织上升到妊娠第20天的723微克/克卵巢新鲜组织，然后在哺乳第1天急剧下降至6微克/克卵巢新鲜组织。与卵巢提取物中松弛素的出现情况和相对水平一致，妊娠大鼠血清中的松弛素水平在妊娠第10天低于2纳克/毫升，在妊娠第20天和第22天约为150纳克/毫升，在哺乳第2天为12纳克/毫升。
