Estimating Potency in High-Throughput Screening Experiments by Maximizing the Rate of Change in Weighted Shannon Entropy.

High-throughput in vitro screening experiments can be used to generate concentration-response data for large chemical libraries. It is often desirable to estimate the concentration needed to achieve a particular effect, or potency, for each chemical tested in an assay. Potency estimates can be used to directly compare chemical profiles and prioritize compounds for confirmation studies, or employed as input data for prediction modeling and association mapping. The concentration for half-maximal activity derived from the Hill equation model (i.e., AC50) is the most common potency measure applied in pharmacological research and toxicity testing. However, the AC50 parameter is subject to large uncertainty for many concentration-response relationships. In this study we introduce a new measure of potency based on a weighted Shannon entropy measure termed the weighted entropy score (WES). Our potency estimator (Point of Departure, PODWES) is defined as the concentration producing the maximum rate of change in weighted entropy along a concentration-response profile. This approach provides a new tool for potency estimation that does not depend on the assumption of monotonicity or any other pre-specified concentration-response relationship. PODWES estimates potency with greater precision and less bias compared to the conventional AC50 assessed across a range of simulated conditions.

Gestrinone inhibits growth of human uterine leiomyoma may relate to activity regulation of ERα, Src and P38 MAPK.

The study was to investigate the effect of gestrinone on the growth of human uterine leiomyoma cells and on the levels and activity of p38, Src and estrogen receptor alpha (ERα). Human uterine leiomyoma cells were cultured and treated with dimethylsulfoxide (DMSO) or a gestrinone concentration gradient. Morphological changes were observed and apoptosis was evaluated. Levels of p38 and phosphorylated-p38 (pp38) were assayed by enzyme-linked immunosorbent assay (ELISA). Levels of ERα and Src were analyzed using real-time RT-PCR and Western blotting. The result showed that gestrinone significantly inhibited the growth of cultured human uterine leiomyoma cells in a concentration- and time-dependent manner, with a 50% inhibitory concentration (IC(50)) value and corresponding 95% confidence intervals (CI) of 43.67 (23.46∼81.32), 27.78 (12.51∼61.68) and 15.25 (7.17∼32.43) µmol/L at 20, 40 and 60h, respectively. Compared with control-treated leiomyoma cells, gestrinone significantly reduced both the expression of ERα (P<0.05) and the levels of phospho-Ser167-ERα (P<0.05). Gestrinone also markedly suppressed the level of phospho-Tyr416-Src (P<0.05). Moreover, gestrinone significantly increased the ratio of phospho-p38/p38 mitogen-activated protein kinase (MAPK) (P<0.05). However, no significant increase in apoptosis or cell cycle arrest was observed (P>0.05) in response to the tested concentrations of 0.1 to 3.0µmol/L. As a conclusion, gestrinone suppresses the proliferation of uterine leiomyoma cells mainly by regulating the activity of ERα/Src/p38 MAPK in a concentration-dependent manner at a low concentration of 0.1∼3.0µM, but not significantly regulating apoptosis. Gestrinone opposes the growth of uterine leiomyoma through multiple genes.

The androgenic anabolic steroid tetrahydrogestrinone produces dioxin-like effects via the aryl hydrocarbon receptor.

For a long time, athletes have used androgenic anabolic steroids (AASs) in an inappropriate and veiled manner with the aim of improving exercise performance or for cosmetic purposes. Abuse of AASs triggers adverse effects such as hepatocarcinogenesis, heart attacks, and aggressive behavior. However, AAS-induced toxicity is not completely understood at the molecular level. In the present study, we showed, by performing a dioxin response element (DRE)-luciferase reporter gene assay, that tetrahydrogestrinone (THG), a popular and potent androgen receptor agonist, has dioxin-like effects. In addition, we showed that THG increased cytochrome P-450 1A1 (CYP1A1) mRNA and protein levels, and enzyme activity. The gene encoding CYP1A1 is involved in phase 1 xenobiotic metabolism and a target gene of the aryl hydrocarbon receptor (AhR). Using the AhR antagonist CH-223191, we also examined whether the effects of THG on DRE activation depended on AhR. Our results suggest that synthetic anabolic steroids may have dioxin-like side effects that can disturb endocrine systems and may cause other side effects including cancer through AhR.

Mechanism of emergency contraception with gestrinone: a preliminary investigation.

BACKGROUND: A previous investigation showed that among 120 healthy women treated with a single oral dose of gestrinone for emergency contraception (EC), there was only one pregnancy. The effect of a single oral dose of gestrinone given for EC on ovarian function and endometrial development was studied. STUDY DESIGN: Healthy fertile women were randomly assigned to Group A (n=8) or Group B (n=7). Gestrinone 5 mg was orally administered to each woman before (Group A) or after (Group B) ovulation. The day of ovulation was determined by transvaginal ultrasound and by urinary luteinizing hormone (LH) measured by enzyme immunoassay (One Step LH Ovulation Test). An endometrial biopsy was performed during implantation. Endometrial maturation and expression of markers of endometrial receptivity were analyzed. The tested markers were integrins alpha(1)beta(1), alpha(4)beta(1) and beta(3). Serum estradiol (E(2)) and progesterone (P) levels in serum were determined by radioimmunoassay, and estradiol receptors and progesterone receptors (PRs) in the endometrium were assessed by immunohistochemistry. RESULTS: Gestrinone administered during the periovulatory period did not affect follicular development, ovulation, menstrual cycle length and E(2) and P levels but decreased the expression of PR in the endometrium. Integrin alpha(4)beta(1) tended to increase after treatment with gestrinone without reaching statistical significance. CONCLUSION: The mode of action of gestrinone used for EC is probably inhibition of implantation by acting on the endometrium rather than inhibition of ovulation.

Effects of gestrinone on uterine leiomyoma and expression of c-Src in a guinea pig model.

AIM: To investigate the effect of gestrinone on uterine leiomyomas and the expression of c-Src, estradiol receptors (ER), and progesterone receptors (PR) in a guinea pig model. METHODS: After being oophorectomized, the guinea pigs were allocated into random groups. The model group was treated with estradiol benzoate (E2) for 16 weeks. In the gestrinone-treated groups, the animals were treated with E2 for 6 weeks in advance, and then in combination with gestrinone for 10 weeks. Histological examination was performed to evaluate whether there were leiomyoma features in the animals. The protein levels of c-Src, phospho-( 416)Src, ER, and PR were assayed by Western blotting and an immunohistochemical method. RESULTS: Morphological changes were observed in the myometrium of the guinea pig model, including an increase of uterine weights, proliferation of uterine smooth muscles, and the formation of nodules. High protein levels of c-Src, phospho- 416Src, ER, and PR were observed in the myometrium of the guinea pig model. In the gestrinone-treated group, there were no nodules observed. The histological features of the myometrium were similar to that of the control group. Low protein levels of c-Src, phospho-(416 )Src, ER, and PR were observed in the gestrinonetreated group. CONCLUSION: The upregulation of c-Src and phospho-(416 )Src indicated that the activity of c-Src is augmented in the uterine leiomyoma model. c-Src was associated with the formation of uterine leiomyomas in the model, and gestrinone markedly suppressed the growth of uterine leiomyomas in the model. Gestrinone inhibited not only the protein expression of ER and PR, but also c-Src and the autophosphorylation of c-Src in the guinea pig leiomyoma model.

[Effect of gestrinone on growth and apoptosis in isolated ectopic endometrium cells in vitro].

OBJECTIVE: To investigate the effects of gestrinone on growth and apoptosis, as well as the expression of phosphatase and tension homologue deleted on chromosome 10 (PTEN) in isolated ectopic endometrium cells in vitro and the underlying mechanisms. METHODS: Ectopic endometrium cells were cultured and exposed to gestrinone of different doses of 0, 10(-6) and 10(-4) mol/L respectively. The inhibition of the cells during 48 hours was determined by methylthiazolyl tetrazolium (MTT) assay, and the cell growth curve was made. Gestrinone was administered to the cells and at 24 hours the morphological changes were observed by transmission electron microscopy and the apoptosis rate, cell cycle and PTEN expression were monitored by flow cytometry (FCM) at the same time. RESULTS: Gestrinone at different concentrations could inhibit the growth and proliferation of ectopic endometrium cells in a dose- and time-dependent manner. The inhibition rate of cell growth after exposed to gestrinone for 8, 16, 24, 32, 40 and 48 h was 99.6%, 87.3%, 79.8%, 62.3%, 51.7% and 44.2% in the 10(-6) mol/L group, and 99.2%, 77.1%, 69.6%, 51.1%, 33.7% and 23.6% in the 10(-4) mol/L group (P < 0.05), and cell growth curve was changed accordingly. After 24 hour exposure to gestrinone from 10(-6) to 10(-4) mol/l, apoptotic changes of cells were observed under transmission electron microscope. FCM showed that after the exposure to gestrinone, the apoptotic rate of ectopic endometrium cells was 1.3% in 10(-6) mol/L group and 15.0% in 10(4) mol/L group. It was significantly increased when compared with the 0 mol/L group, the apoptotic rate of which was 0% (P < 0.05). The level of PTEN expression of the ectopic endometrium cells was 60.6% after treated with 0 mol/L gestrinone, while in 10(-6) and 10(-4) mol/l groups the level of PTEN expression was increased to 75.3% and 85.7%, significantly higher than that of the 0 mol/L group (P < 0.05). CONCLUSION: Gestrinone can significantly inhibit the growth and proliferation of ectopic endometrium cells, and this effect was related to increase of PTEN expression.

Tetrahydrogestrinone is a potent androgen and progestin.

Tetrahydrogestrinone (THG) was recently identified as a novel steroid used illicitly to improve athletic performance. Although its structure is closely related to gestrinone, a 19-nor progestin, and resembles that of trenbolone, THG was never marketed, so information on its hormonal properties is not known. In this study, we demonstrate that THG is a highly potent androgen and progestin in a yeast-based in vitro bioassay system expressing human androgen and progesterone receptors. It has no estrogenic activity and no antagonism for any of the three steroid receptor classes.

Avaliaçäo dos parâmetros de resposta clínica, hormonal e ultra-sonográfica do tratamento do leiomioma uterino com gestrinona / Clinical, hormonal and ultrasound evaluation after leiomyoma clinical treatment with gestrinone

OBJETIVOS: Avaliar a resposta clínica de pacientes com miomatose tratadas com gestrinona. PACIENTES E MÉTODOS: Foram 14 mulheres com idade entre 24 e 42 anos, com miomatose sintomática, tratadas com gestrinona 15mg/sem durante 6 meses. RESULTADOS: O volume uterino médio, determinado por US, foi de 454,57cmü antes e 264,66cmü depois do tratamento. Em 5 pacientes o volume uterino diminuiu mais de 30 por cento (média de 699,2cmü antes para 369,4cmü depois do tratamento). Em 6 pacientes o volume uterino foi reduzido entre 10 e 30 por cento e em 3 pacientes o volume foi reduzido em menos de 10 por cento. Houve uma relaçäo positiva entre volume uterino pré tratamento e porcentagem de reduçäo. Os níveis de LH e FSH näo diferiram significativamente antes ou depois do tratamento, enquanto os níveis de PRL e E2 reduziram-se significativamente. Esta reduçäo foi maior nas pacientes que exibiram uma melhor resposta clínica ao tratamento. CONCLUSOES: A gestrinona pode ser usada no tratamento clínico da miomatose uterina em pacientes na pré menopausa, como alternativa clínica ao tratamento cirúrgico. Os níveis de estradiol säo um bom fator preditivo de boa resposta de reduçäo uterina

Gestrinone inhibits macrophage function and mitogen-stimulated lymphocyte proliferation in vitro.

Clinical and experimental evidence supports the hypothesis that some steroidal drugs with androgenic effects might influence the immune system. The present study investigated whether gestrinone is able to affect macrophage and lymphocyte activity in vitro. Macrophage function was determined by phagocytosis of fluorescent microspheres, whilst lymphocyte proliferation was assessed by cell counting. Macrophage phagocytosis was evaluated after an overnight incubation in the presence or absence of gestrinone at serial dilutions; lymphocyte proliferation was detected in basal conditions and after stimulation with Concanavalin A (Con A) in the presence or absence of gestrinone. The results of this study showed that gestrinone significantly inhibited macrophage phagocytosis at the concentrations of 10(-8), 3 x 10(-8) and 10(-7) M. Furthermore, a significant suppression of lymphocyte blastogenesis was observed when lymphocytes were incubated with gestrinone at the concentration of 10(-7) M for 6 days. The biological significance of gestrinone as an inhibitor of immune functions under experimentally defined conditions is discussed in relation to its potential mechanism for fertility enhancement.

Endometriosis: medical therapy.

The management of women with endometriosis is complex and necessitates individualization of patient care. The most commonly used medical therapies are danazol, GnRH agonists, medroxyprogesterone acetate and gestrinone. Studies to date have shown these drugs to have equal efficacy in terms of reduction in laparoscopic score and relief of symptoms. However, their side-effects make them unsuitable for long-term use. The addition of low dose hormone replacement therapy to GnRH agonist regimens may allow prolonged use but the current cost of these agents is high. Low dose oral contraceptive pills deserve further investigation. The role of medical treatment for women with endometriosis and infertility is controversial. There is no place for hormonal therapy in such women with stage I or II disease. When expectant management fails, gamete intrafallopian transfer offers excellent results. For those with stage III or IV disease, surgery is preferable with adjunctive medical therapy in selected cases. If pregnancy does not ensue, in vitro fertilization and embryo transfer are the next line of management, and results are optimized by prior medical therapy and aspiration of endometriomas. Major advances have been made in the medical management of endometriosis. However, current treatment strategies are ineffective in eliminating the disease in most women. New approaches are required in both basic and clinical research in order to finally eradicate this often devastating disease.

No inhibitory effects of gestrinone and medroxyprogesterone acetate on the estrogen production by ovaries of hypophysectomized rats stimulated by gonadotropins.

The in vivo effects of gestrinone (R2323) and medroxyprogesterone acetate (MPA) on the estrogen production by rat ovaries were investigated. Hypophysectomized immature female rats treated with 2.5 or 5 IU of pregnant mare serum gonadotropin (PMS) were daily given vehicle only, gestrinone (0.5 mg/kg body weight) or MPA (10 mg/kg body weight), and the activities of 3 beta-hydroxysteroid dehydrogenase, 17 alpha-hydroxylase, 17, 20-lyase, 17 beta-hydroxysteroid dehydrogenase and aromatase in ovaries of these rats were measured. Gestrinone suppressed the 3 beta-hydroxysteroid dehydrogenase activity and increased activities of 17 alpha-hydroxylase, 17, 20-lyase and aromatase in ovaries stimulated by 5 IU of PMS, while MPA suppressed activities of 17 alpha-hydroxylase and aromatase in these ovaries. On the other hand, the aromatase activity in ovaries stimulated by 2.5 IU of PMS was suppressed by gestrinone and increased by MPA, and neither gestrinone nor MPA affected the production of aromatizable androgens from progesterone by these ovaries. Thus, gestrinone and MPA administrated in vivo showed divergent influences on steroidogenic enzyme activities in ovaries, but they did not affect the serum concentration of estradiol-17 beta. The present results suggest that neither gestrinone nor MPA reduced estrogen production by the rat ovary under the gonadotropin stimulation although they influenced some process of its steroidogenesis.

The induction of amenorrhoea.

A survey has shown that many women favour eliminating menstruation and it has been suggested that therapeutic induction of amenorrhoea might be an advantage in female personnel mobilised for war. The traditional method has been to take the oral contraceptive pill continuously. This produces weight gain and other side-effects; spotting and breakthrough bleeding can be a problem initially. The method is however cheap. The Gonadotrophin Releasing Hormone (GnRH) analogue, goserelin, is extremely effective, produces less side-effects, but it is very expensive. Two synthetic steroids, danazol and gestrinone, are moderately effective, have a variety of prominent side-effects and are also quite expensive. With all these drugs normal menstruation resumes in the cycle after they are discontinued. Although goserelin has many advantages over the continuously taken contraceptive pill, its cost precludes it from consideration as a means of eliminating menstruation.

PIP: The Royal Army Medical Corps (RAMC) of the UK is considering offering women in the Army the option of inducing amenorrhea especially those in war. Logistics problems of supplying sufficient sanitary protection makes inducing amenorrhea in these women an advantage. It is important that the Royal Army not force servicewomen ready for war to agree to chemical induction of amenorrhea, however. A survey of civilian women shows that 80% liked the notion of eliminating menstruation. continuous combined oral contraceptive (COC) therapy induces amenorrhea, but it poses some side effects including bleeding and spotting, 2 kg weight gain, breast tenderness, depression, and headaches. 12 weeks of COC therapy costs range form 2 to 6 pounds. The synthetic androgen used to treat endometriosis, danazol, may also induce amenorrhea at daily doses of 800 mg. It causes various side effects including reduced breast size, flushing, sweating, loss of libido, acne, weight gain, edema, hirsutism, and voice change. 12-week danazol therapy costs about 200 pounds. Another drug with androgenic, antigonadotrophic, antiestrogenic, and antiprogestogenic properties which is also used to treat endometriosis, gestrinone, in another possible amenorrhea inducer at 2 doses of 2.5-5 mg/week. Side effects are similar to those of danazol. In 1 study, all 20 patients developed acne and seborrhea. Its 12 week costs are considerably more than danazol and COC therapy (450 pounds). Intermittent administration of 2 gonadotropin releasing hormone (GnRH) analogues, buserelin and goserelin, suppresses production of gonadotropins. Health workers need to inject 3.6 mg goserelin every 28 days while they administer buserelin subcutaneously or intranasally. the leading side effect on both GnRH analogues is not flushes. 12-week therapy is about 375 pounds. Fertility is restored after discontinuation of all the aforementioned therapies. The GnRH analogue goserelin is the most effective therapy, but the cost factor causes the Royal Army to favor COCs.

Antiestrogenic effect of gestrinone as an inhibitor of [3H]-estradiol binding to nuclear type II sites.

Gestrinone has a biophysical antiestrogenic effect. But the mechanism of its antiestrogenic effect is not clear. Gestrinone blocked the increase of estrogen binding of nuclear type II sites and uterine weight in the estrogen-treated immature rabbit. Competitive assays indicated that gestrinone, at low concentrations (0.4 approximately 4 nM), inhibited [3H]-estradiol binding to nuclear type II sites. This inhibitory effect was the same as the addition of 20 microM diethyl-stilbestrol. This inhibition with gestrinone on [3H]-estradiol binding to nuclear type II sites appeared only when used at concentrations less than an equivalent molar of [3H]-estradiol. Time course analysis of the gestrinone binding inhibition showed that within the first 6 min gestrinone did not inhibit specific [3H]-estradiol binding to nuclear type II sites. This gestrinone-mediated inhibition was not observed in soluble fractions such as the cytosolic and KCl-extracted nuclear binding sites. These results suggest that gestrinone acts primarily on the nuclear fraction and then it operates the inhibitory mechanism on estradiol binding to nuclear type II sites.

Progesterone protects oocytes from premature degeneration within the follicle.

The present study was designed to determine the effects of gestrinone (R2323) in the process of follicle rupture and oocyte maturation and degeneration in an in vitro perfused rabbit ovary model. In the first experiment, R2323 at 10(2), 10(3), or 10(4) ng/ml was added to the perfusate of one ovary. The contralateral control ovary was perfused simultaneously with medium alone. Thirty minutes after the onset of perfusion, 50IU of human chorionic gonadotropin (hCG) was added to the perfusate of both ovaries. All ovaries exposed to R2323 plus hCG or hCG alone ovulated. The addition of R2323 to the perfusate did not affect the ovulatory efficiency of ovaries treated with hCG. No significant difference in the percentage of ovulated ova or follicular oocytes demonstrating germinal vesicle breakdown was seen with R2323 treatment. R2323 increased the degeneration rate of ovulated ova in a dose-dependent fashion. In the second experiment, in which experimental ovaries were perfused with R2323 (10(4) ng/ml) plus progesterone (10(3) ng/ml) and the control ovaries with R2323 (10(4) ng/ml) alone ovulation occurred in response to hCG. However, the addition of progesterone to the perfusate reduced the degeneration-inducing effect of R2323 on both ovulated ova and follicular oocytes. In conclusion, R2323 appears to act as an antiprogesterone, thereby promoting the degeneration of oocytes. The increased production of progesterone in the preovulatory follicle following the gonadotropin surge protects oocytes from premature degeneration within the follicles.

Luteolytic effect of the antiprogestin and antiglucocorticoid agent RU486 in rats.

Ovarian cells of pregnant rats were cultured with synthetic progestins (R5020, R2323), dexamethasone and RU486. Progesterone and 20 alpha-hydroxy-pregn-4-en-3-one (20 alpha-dihydroprogesterone) in the medium were measured by specific radioimmunoassay. Both R5020 and R2323 increased concentrations of these intrinsic progestins. RU486 decreased concentrations of progesterone, however, the addition of R5020 or R2323 counteracted this action. Immature hypophysectomized rats treated with pregnant mare serum gonadotropin (PMS) and human chorionic gonadotropin (hCG) were administered with RU486; the serum levels of progesterone and 20 alpha-dihydroprogesterone tended to decrease. R5020 and R2323 inhibited the effect of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), whereas RU486 did not. Inhibition of the cholesterol side chain cleavage enzyme (CSCC) by RU486 was more marked than that by R5020 or R2323. These results show that RU486 decreases progesterone synthesis in cultured ovarian cells. A part of the mechanism may involve an inhibition of CSCC.

Modulation of steroid production in goat ovarian cells: effect of progestins and antiprogestins.

Effect of various synthetic progestins and antiprogestational compounds on progesterone (P) and estradiol (E) production by isolated goat ovarian granulosa (G) and corpus luteum (CL) cell types was studied in vitro. Steroid production was studied either under basal conditions or after stimulation with follicle stimulating hormone (FSH) in the presence of aromatase substrate, androstenedione (A). None of the progestins had any significant effect on basal P and E production by either cell types during 48 hour of culture. The FSH and A - induced increase in P and E production was significantly inhibited following concommitant treatment with synthetic progestins at concentrations higher than 10(-7) M. The added progestins had no effect on G and CL cell viability. None of the antiprogestational compounds had any significant effect on basal steroid production in either of the cell types. Furthermore, the higher concentrations of three antiprogestins namely RMI 14156, STS 557 and isomer 201 of RMI 12936, were found to stimulate significantly the basal as well as FSH + A - induced production of estradiol in both the cell types. In contrast, the other two antiprogestins tested were found to stimulate the gonadotropin + A - induced production of P. These results indicate that exogeneous progestins directly inhibit the gonadotropin + androstenedione - induced steroid production by G and CL cells in vitro. Moreover, different antiprogestin had different effect on the modulation of steroid production.

[Studies on endocrine therapy of endometriosis].

GnRH agonist and synthetic steroid such as Danazol, Medroxyprogesterone acetate (MPA) and Gestrinone are useful for the treatment of patients with endometriosis. These compounds induce atrophy and regression of endometriotic tissue, but the action mechanisms are still unclear. The present study, therefore, was undertaken to elucidate the mechanisms of these compounds in the treatment of endometriosis. In addition, a combination therapy with these compounds for endometriosis was also evaluated with an experimental animal model. Effects of GnRH agonist, Danazol and GnRH/Danazol combination on experimental endometriosis were evaluated in female rats. Endometrium autotransplanted under the renal capsule markedly decreased in size following castration. Histologic examination indicated atrophy and regression of the endometrial explant. The changes of endometrial explant were also induced by GnRH agonist, Danazol and combination treatment. However, a combination therapy with GnRH agonist and Danazol (93%) was shown to be superior to GnRH agonist (65%) and Danazol alone (45%) to induce atrophy and regression of experimental endometriosis. As expected, GnRH agonist significantly decreased serum E2, but Danazol did not at all. It is suggested that a combination therapy with GnRH agonist and Danazol may be a potential modality in the treatment of endometriosis. In order to evaluate whether Danazol, MPA, and Gestrinone has a direct inhibitory effect to synthesize estrogen, immature female rats were hypophysectomized and the ovaries were stimulated by a daily PMS injection. Administration of Danazol to the rats for two weeks stimulated the synthesis of 17, 20-lyase, 17 beta-HSD and aromatase activity, but did not inhibit any enzyme activities.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of gestrinone on serum lipid and lipoprotein levels in women with endometriosis].

Gestrinone (G) was given to 12 females with endometriosis in weekly doses of 5 or 10mg for 4 to 6 months, and the change in serum lipids and lipoproteins was analysed. G decreased total cholesterol by 20% (p less than 0.05), triglycerides by 36% (p less than 0.05), phospholipids by 28% (p less than 0.01) and lipid peroxides by 34% (p less than 0.05), among which reductions in them were statistically significant when compared with the pretreatment levels. Levels of high density lipoproteins (HDL) also fell: HDL-cholesterol by 41% (p less than 0.01), HDL-triglycerides by 49% (p less than 0.05) and HDL-phospholipids by 38% (p less than 0.01) which were significant. Concurrently apolipoproteins (Apo) and lecithin-cholesterol acyltransferase activity (LCAT) decreased: Apo A-I by 31% (p less than 0.01), Apo A-II by 13% (p less than 0.05) and LCAT by 53% (p less than 0.05), which were significant. In contrast, there were few changes in the levels of low density lipoproteins (LDL) and Apo B. There was also little effect on very low density lipoproteins (VLDL) except VLDL-triglycerides which decreased by 52% (p less than 0.05). Meanwhile free fatty acids increased by 61% (p less than 0.05). Therefore, the atherogenic index defined as the ratio of LDL-cholesterol to HDL-cholesterol rose as much as 92% (p less than 0.01) of the initial value in 24 weeks of medication. When these results were examined with respect to the 5 and 10mg administration group, dose-dependent effects were observed, but these were not marked.(ABSTRACT TRUNCATED AT 250 WORDS)