We measured serum corticosteroid-binding globulin (CBG) and hepatic CBG mRNA from individual hamsters throughout pregnancy and during decidualization. Serum CBG levels were determined by 3H-cortisol binding assay, and hepatic CBG mRNA levels were measured by Northern blots and solution hybridization assays, using a 32P-labeled cRNA probe derived from a rat CBG cDNA. There was a positive relationship between hepatic CBG mRNA levels and serum CBG levels during pregnancy. Both parameters increased significantly from the time of mating (cycle Day 4) to pregnancy Day 4, showing that CBG synthesis and secretion increased prior to implantation (Day 4). After implantation, serum CBG and hepatic CBG mRNA rose further from pregnancy Day 4 to a peak on Day 14, then decreased before parturition on Day 16. The prepartum decline in hepatic CBG mRNA preceded the fall in serum CBG. Decidualization on pseudopregnancy Day 4 resulted in an increase in serum CBG and hepatic CBG mRNA. Hepatic CBG mRNA increased from Day 5 to Day 7, and serum CBG increased progressively from Day 5 through Day 9 after uterine decidualization in the hamster. The present results demonstrate that the pattern of serum CBG observed in the pregnant hamster follows closely that of hepatic CBG mRNA. A signal emanating from uterine decidual tissue appears to be important in the regulation of hepatic CBG synthesis and secretion during midpregnancy, but other unknown factors appear to be involved in controlling CBG during the early and late stages of pregnancy.

Green finance contributes significantly to the openness and transparency of carbon quota trading prices, which is conducive to the development of green technology innovation. With known carbon quota trading prices, we construct game‐based operational research models to analyze fixed‐fee and mixed‐fee cross‐licensing strategies for green technologies between two competing firms under the cap‐and‐trade policy. We compare the equilibrium outcomes of no‐licensing, fixed‐fee, and mixed‐fee cross‐licensing strategies. The findings reveal that product pricing under the fixed‐fee cross‐licensing strategy is beneficial to consumers. The mixed‐fee cross‐licensing strategy is optimal in terms of firms' total profits. When the degree of product substitutions is large and the improvement in carbon emissions is small, firms are more inclined to the no‐licensing strategy. We further introduce the revenue‐sharing contract, which can extend the Pareto improvement domain and improve the performance of green technology cross‐licensing strategies.

In this study we measured corticosteroid-binding globulin (CBG) mRNA levels in liver and various nonhepatic tissues of pregnant and nonpregnant hamsters. The N-terminal amino acid sequence (37 residues) of hamster CBG was determined and compared with published cDNA-deduced sequence information for rat and human CBG. Hamster CBG showed considerable sequence homology with both rat (70%) and human (59%) CBG. Because of the high level of homology, we were able to use a cRNA prepared from a rat CBG cDNA as a probe in Northern blot and solution hybridization analyses. Northern blots of hamster and rat liver RNA extracts revealed that the rat CBG cDNA probe hybridized to RNAs that were the same size in rats and hamsters. Further, the Northern blot showed that pregnant hamster liver contained substantially more CBG mRNA than nonpregnant hamster liver. The relative amounts of CBG mRNA in pregnant and nonpregnant hamster livers were compared using a solution hybridization assay. Slope-ratio analysis of the hybridization data revealed that pregnant hamster liver (day 14) contained 40-fold more CBG mRNA than nonpregnant hamster liver. When other tissues (kidney, spleen, small intestine, and decidual tissue) were assayed for CBG mRNA, a small amount of hybridization was detected by solution hybridization. However, Northern blot analysis of RNA extracts from nonhepatic tissues showed that the hybridizable sequences did not migrate at the same position as mature CBG mRNA. These results indicate that the observed increase in serum CBG during hamster pregnancy is largely attributable to an increase in hepatic CBG mRNA.

No abstract