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This paper deals with the quantitative determination of the total alkaloids in Radix Gelsemii and its preparation by colorimetric method with acid dye. It is shown that the mean contents of total alkaloids in Radix Gelsemii and its alkaloids injection were 0.621% and 5.02 mg/ml respectively, and the mean recovery was 96.87%.

Chronic natural or synthetic estrogen treatment of Syrian golden hamsters leads to the development of malignant renal neoplasms. In the present study, morphological and immunohistochemical studies were performed to further characterize the estrogen-induced hamster renal tumors. The neoplasms were composed of two distinct cell populations: a large-cell component that appeared highly epithelial, and a poorly differentiated small-cell component. Importantly, both cell types had epithelial characteristics, since they contained desmosomes at their cell surfaces. However, the large-cell component possessed additional epithelial features such as microvilli, intracytoplasmic lumens, and cilia. Comparative studies of renal tumors and developing renal tissue from fetal and newborn hamsters revealed remarkable histological similarities. Morphologically, the large tumor cells resembled early metanephric tubules and the small tumor cells were very similar to the blastemal cells of the developing kidney. The earliest tumor foci were found after 4.5 months of treatment. They were consistently found in the kidney interstitium in proximity to large arteries. Immunohistochemical staining for intermediate filaments in developing fetal and newborn kidneys demonstrated cytokeratin in renal tubules, desmin in blastemal cells, and vimentin in stromal cells. Estrogen-induced renal tumor cells uniquely possessed reactivity for all three intermediate filaments, clearly demonstrating their epithelial and mesenchymal characteristics. Based on their morphological resemblance to developing embryonic kidney cells and the presence of both epithelial and mesenchymal intermediate filaments, our findings provide strong evidence that the cell of origin of this malignant tumor is a precursor cell that is committed to an epithelial differentiation pathway.

Plasma levels of the acute-phase reactant, C-reactive protein (CRP), increase up to one thousand-fold as a result of trauma or inflammation. CRP binds to phosphorylcholine (PC) in a calcium-ion dependent manner. The structural homology between PC and the major phospholipid component of surfactant, dipalmitoyl phosphatidylcholine (DPPC), led to the present study in which we examined if CRP levels might be increased in patients with adult respiratory distress syndrome (ARDS), and subsequently interfere with surfactant function. Our results showed that CRP levels in the bronchoalveolar fluid (BALF) was increased in patients with ARDS (97.8 +/- 84.2 micrograms/mg total protein vs. 4.04 +/- 2.2 micrograms/mg total protein in normals). Our results show that CRP binds to liposomes containing DPPC and phosphatidylglycerol (PG). As a result of this interaction, CRP inhibits the surface activity of a PG-DPPC mixture when tested with a Wilhelmy surfactometer or with the Enhorning pulsating bubble apparatus. Furthermore, the surface activity of a clinically used surfactant replacement, Surfactant TA (2 mg/ml), was also severely impaired by CRP in a dose-dependent manner (doses used ranging from 24.5 to 1,175 micrograms/ml). In contrast, human serum albumin (HSA) at 500 and 900 micrograms/ml had no inhibitory effect on Surfactant TA surface activity. These results suggest that CRP, although not an initiating insult in ARDS, may contribute to the subsequent abnormalities of surfactant function and thus the pathogenesis of the pulmonary dysfunction seen in ARDS.

We have studied the irreversible binding of [14C]estradiol to hamster liver and kidney microsomes of castrated hamsters. The binding of estradiol metabolites to kidney microsomes was approximately 25 times lower than seen for liver microsomes, and was not affected by increases in protein or substrate concentration. Our results indicate that this irreversible binding, covalent in nature, is dependent on the metabolism of estrogens to catechols since the absence of NADPH markedly reduces this binding. The irreversible binding was inhibited nearly 70% by addition of catechol-O-methyl transferase (COMT) and S-adenosylmethionine (SAM). Ascorbic acid also inhibited the binding to 85% in a dose-dependent manner. Utilizing a displacement assay to assess the relative covalent binding of different stilbene and steroidal estrogens with homologous radiolabeled hormones, we found that only indenestrol B exhibited greater ability than diethylstilbestrol (DES) to displace [14C]DES from hepatic microsomal proteins. Except for hydroxypropiophenone and beta-dienestrol, all of the stilbene estrogens studied displaced the radioactive DES binding from these liver proteins to a greater extent than estradiol at comparable concentrations. A marked difference was observed in the ability of alpha- and beta-dienestrol to displace [14C]DES. Using radioinert steroidal estrogens to displace [14C]estradiol, we observed that both estriol and deoxoestrone were significantly less effective in displacing radiolabeled estradiol from liver microsomal proteins. Only ethinyl estradiol and 2-hydroxyestradiol displaced greater than 50% of the radioactive hormone at 1-fold excess concentrations. Interestingly, 11 beta-methoxyethinyl estradiol (Moxestrol) exhibited essentially the same ability to bind liver microsomal proteins as estradiol. When estrone and 2,4-dibromoestradiol were used as substrates together, we found the latter compound to be inactive as a substrate for estrogen hydroxylase (ESH) and additionally inhibited the metabolism of estrone to form the catechol metabolite. Data presented herein suggest that the chemically reactive estrogen metabolites responsible for covalent binding of both stilbene and steroidal estrogens are quinoids derived from catechols formed earlier in metabolism. Except for ethinyl estradiol which is a good substrate for liver, but not kidney microsomal ESH, the carcinogenicity data for the hamster kidney with respect to these estrogens is consistent with the covalent binding data presented.

Based on the experimental studies presented herein, we have concluded there are hormonal and carcinogenic aspects to estrogens, both natural and synthetic, which are involved in renal tumorigenesis in the hamster. Hormonal aspects related to this tumor system are based on the presence of specific estrogen receptor in the untransformed kidney which is elevated by prolonged estrogen treatment. Moreover, antiestrogens, which inhibit estrogen receptor complex binding activity, completely block renal tumor induction by estrogens. Finally, estrogens were found to induce progesterone receptor in the hamster kidney and this induction can be inhibited by androgens and antiestrogens. Carcinogenic aspects related to renal tumorigenesis are suggested by the marked suppression of estrogen-induced kidney tumors by alpha-naphthoflavone. In addition, ethinyl estradiol, as potent an estrogen in the hamster as either DES of 17 beta-estradiol, induced only a very low renal tumor incidence. The finding that aryl hydrocarbon hydroxylase activity in the hamster kidney, but not the liver, is depressed markedly by estrogens and enhanced by androgenic hormone suggests involvement of the microsomal monooxygenase system in affecting estrogen metabolism and ultimately perhaps its carcinogenicity.