Biomedical subjects

J Spona

Publications and source records attributed to J Spona.

At least 181 records · Page 10Linked to original sources

PubMed1982

Differential stimulation by 17 beta-estradiol and synthetic estrogens of progesterone-receptor and of translocation of estrogen-receptor in rat pituitary and uterus.

Central and peripheral actions of physiological and synthetic estrogens with elevated biological potencies were investigated. The synthetic estrogens were 1,3-diacetoxy-17 alpha-ethinyl-7 alpha-methyl-1,3,5(10)-estratrien-17 beta-ol (DM-EE2) and 1,3-dibenzoyloxy-17 alpha-ethinyl-7 alpha-methyl-1,3,5(10)-estratrien-17 beta-ol (DB-EE2). More prolonged nuclear retention of the estrogen-receptor was found after application of DM-EE2 and DB-EE2, than in the pituitary and uterus after injection of the same dose of 17 beta-estradiol (E2). Longer nuclear retention of the estrogen-receptor was observed in the pituitary after DB-EE2 application and in the uterus after DM-EE2 than in E2-treated rats. Pituitary progesterone-receptor was raised to 706% of controls by treatment with E2 and 1187% and 2308% after injection of DM-EE2 and DB-EE2, respectively. On the other hand, only 208% and 225% stimulation, respectively, of progesterone-receptor was observed in the uterus after treatment with the synthetic estrogens DM-EE2 and DB-EE2. In vitro cytosol receptor binding assays revealed low relative binding affinities of the synthetic estrogens compared to E2. The results may be explained by the hypothesis that differences in biological activity of estrogens may be caused by different metabolic and/or cellular events localized in distinct target organs or by altered affinity of the nuclear estrogen receptor complex to chromatin receptor sites due to a change in receptor conformation.

Animals↗

PubMed1982

The relationship of prolactin in cord blood, gestational age and respiratory compliance after birth in newborn infants.

In 29 healthy newborns (gestational age 30-41 weeks) and 7 newborns with respiratory distress syndrome (gestational age 28-31 weeks) the prolactin levels in the cord blood and respiratory compliance was measured. Prolactin was determined by radioimmunoassay, the respiratory compliance was measured with the airway occlusion technique in spontaneously breathing newborns and with injection of known volumes and measuring the airway pressure in newborns with ventilatory support. In healthy newborns prolactin and gestational age were significantly correlated (r = 0.62, p less than 0.001), while prolactin did not correlate with respiratory compliance (r = 0.22, n. s.). Comparing 5 healthy newborns and the 7 RDS infants with prolactin values below 170 ng/ml, there was no significant difference in the prolactin levels, but in the compliance values. We conclude that prolactin does not directly influence lung maturation, but is associated with gestational age.

Fetal Blood↗

PubMed1981

Inhibition by tamoxifen of estrogen-stimulated accumulation of preprolactin messenger ribonucleic acid.

Estrogens are involved in the stimulation of prolactin synthesis in the rat anterior pituitary. After 5 days of treatment with 17beta-estradiol, strong enhancement of [3H]leucine incorporation into prolactin an stimulation of translatable preprolactin mRNA, respectively, were noted. Increase in prolactin synthesis was found following daily application with estriol and the synthetic estrogen 1,3-dibenzoyloxy-17 beta-methyl-1,3,5(10)-estratrien-17 beta-ol (DB-EE2). The antiestrogen tamoxifen (trans-1-(p-beta-dimethylaminoethoxyphenyl)-1,2-diphenylbut-1-ene) was demonstrated to inhibit estradiol-stimulated prolactin syntheses. Antagonistic effects of tamoxifen were dose dependent. Low loses of the antiestrogen were already sufficient to suppress 17 beta-estradiol-enhanced levels of prolactin mRNA. On the other hand, estriol potentiated 17 beta-estradiol-stimulated levels of serum prolactin and prolactin synthesis. Our results add further information about the transcriptional control by estrogens and demonstrate inhibitory actions of antiestrogens on distinct regulatory levels of protein synthesis in the rat pituitary.

Animals↗

PubMed1981

[Hypophyseal reaction state during oral contraceptiva (author's transl)].

In 5 normocyclic women, firstly taking a conventional oral contraceptive, Neogynon (50 mcg EE + 250 mcg levo-norgestrel) for 6 months, the levels of LH, 17 beta-E2 and progesterone did not rise after changeover to a dose-reduced pill, Microgynon 30 (30 mcg EE + 150 mcg levo-norgestrel). This fact indicates maintained central suppression. Examination of the hypothalamic-hypophyseal axis by the Gn-RH test (50 mcg) with Microgynon 30 showed negative results during the first treatment cycle in 13 out of 18 women. In the 6th treatment cycle only 7 Gn-RH non-reactive women were observed and after stimulation with 100 mcg Gn-RH only 5 women remained with negative Gn-RH tests. Of the 20 women who took conventional oral contraceptives over a period of 6 months to 6 years (7 took Eugynon: 50 mcg EE + 500 mcg D,L-norgestrel, 5 Lyndiol: 75 mcg mestranol + 2.5 mg lynoestrenol, 8 Neogynon, only one from the Neogynon group showed a positive result. On the other hand there was a positive reaction in 4 out of 7 women using the two step dose-reduced preparation Sequilar (11 tablets of 50 mcg EE + 50 mct levo-norgestrel and 10 tablets of 50 mcg EE + 125 mcg levo-norgestrel).

Adult↗

PubMed1981

[The efficacy of gestoden (delta 15-d-norgestrel) as ovulation inhibitor (author's transl)].

Two single-phase combined low-dosage oral contraceptive preparations were tested with respect to their effects on functional parameters of the menstrual cycle. Twenty young women with a normal biphasic menstrual cycle took part in this random study. Evaluation of cervical function, consistency and crystallisation ability of the cervical mucous and of the karyopyknosis index as well as radioimmunoassay of the serum levels of LH, FSH, HPRL, 17-beta-oestradiol and progesterone were carried out consecutively as from the 8th day over the duration of one control cycle and one in which contraceptive as administered. Preparation I (SH D 356 A) contained 75 micrograms delta 15-d-norgestrel (Gestoden) + 30 micrograms ethinyloestradiol. Whilst preparation II (SH D 356 B) contained 75 micrograms d-norgestrel + 30 micrograms ethinyloestradiol. Both substances successfully inhibited ovulation, whereby the former achieved a markedly greater suppression of function with regard to all parameters and, yet good menstrual cycle control was maintained. Hence, gestoden enables the content of active components in oral contraceptives to be reduced even further without detracting from the safety of the technique.

Adult↗

PubMed1981

[Endocrine interrelationships in patients with malignant testicular tumours (author's transl)].

Testicular function was investigated in 40 patients with malignant testicular tumours of different histology and tumour stage, by spermatological and endocrinological analyses. In patients without ectopic production of beta-HCG in the tumour tissue a hypergonadotropic tubular disfunction of the testis was present, resulting in elevated plasma FSH concentrations and moderate to severe oligozoospermia. Ectopic production of beta-HCG in the tumour stimulates the secretion of 17 beta-oestradiol, particularly in the Leydig cells, which suppresses pituitary gonadotropin secretion via negative testicular pituitary feedback. Spermatological analyses showed severe spermatogenetic disorders. Prolactin levels, however, were not altered in patients with testicular cancer.

Adolescent↗

PubMed1981

[Steroid receptor levels in human breast carcinomas in relation to serum hormone levels in postmenopausal patients (author's transl)].

Serum levels of LH, FSH, HPRL, oestradiol, progesterone and testosterone were determined by radioimmunoassay in 45 postmenopausal patients in the morning before they were operated on for primary breast cancer. Cytosol oestradiol - (E2R) and progesterone receptor (PgR) levels were estimated by Scatchard plot analysis of saturation assays using the charcoal method. When serum hormone levels and receptor contents were correlated according to the distribution free test of Spearman, all correlations were found to be insignificant, with the exception of E2R/PgR (p less than 0.001).

Aged↗

PubMed1981

[Effect of ear-acupuncture on the LH-concentration in serum in patients with secondary amenorrhea (author's transl)].

In 13 patients at an age of 17 to 26 years with intermittent or secondary amenorrhea an attempt was made to stimulate the pituitary gland by ear-acupuncture. The objective parameter for the comparison was the concentration of the luteinizing hormone (LH) in the serum during acupuncture and the LH-RH-releasing test. 6 of these patients were subjected to a so-called "placebo-acupuncture" to perform a blind-test. The results showed, that ear-acupuncture caused a significant decrease of the LH-concentration in the serum. The clinical results showing a positive effect of ear-acupuncture in the mentioned types of amenorrhea could therefore be explained as a rebound phenomenon.

Acupuncture Therapy↗

PubMed1981

Effect of cyproterone/acetate (SH-714) on plasma prolactin in patients with prostatic cancer.

Plasma prolactin was measured in 10 patients with prostatic cancer during treatment with cyproterone acetate (300 mg/week i.m.) Prolactin was assayed during a six month period at weekly intervals during the first 4 weeks and then at monthly intervals. Orchiectomy was not carried out. After 6 months prolactin levels were elevated compared with pre-treatment levels. It is concluded from this study that cyproterone acetate interferes with prolactin secretion by the pituitary gland.

Aged↗

PubMed1981

Inhibition of LH-release by synthetic analogues of LH-RH in rat pituitary cell culture.

Conditions for testing the inhibitory activity of synthetic analogues of LH-RH in monolayer cultures of rat pituitary cells were optimized. Nine synthetic derivatives of LH-RH were tested to evaluate their inhibitory dose50(ID50) values. The peptide antagonists tested included linear, branched-chain, dimeric and tetrameric derivatives of LH-RH, Ac-D-Phe1, D-Cpa2, D-Trp3,6-LH-RH (analogue V) was found to be the most effective competitive inhibitor of the series with an ID50 value of 6 x 10(-9)M in the presence of 10(-9) M LH-RH. The kinetics of the LH-RH-blocking action of two inhibitors were also studied. Both the linear (analogue I) and the dimeric (analogue VI) peptide showed immediate inhibition of HL-release. Prolonged inhibitory activity of the same two peptides was observed when cells were incubated with LH-Rh subsequent to preincubation with the inhibitors.

Animals↗

PubMed1981

Effects of antidepressant treatment with clomipramine on hormonal responses to thyrotropin-releasing hormone and insulin-induced hypoglycemia: implications for the "monoamine-hypothesis".

Neuroendocrine test were carried out to study effects of clomipramine treatment in 24 unipolar depressed women. Clomipramine (50-150 mg/day) increased the response of prolactin and thyrotropin to stimulation by thyrotropin-releasing hormone (TRH), while no response of growth hormone (HGH) to TRH was seen. Clomipramine decreased the response of HGH to insulin, while the responses of prolactin and cortisol to insulin were not affected. The findings suggest that the neuroendocrine and antidepressant effects of clomipramine cannot be accounted for entirely on the basis of monoaminergic mechanisms.

Biogenic Amines↗

PubMed1981

[Tumor histology and steroid receptors in breast carcinoma].

In Specimens of 115 patients with breast cancer 4 tumorparameters (tumorsize, tumorboder, nucleargrade, lymphocytic stromal reaction) 3 features of regional lymphnodes (sinushistiocytosis, T-cellreaction, lymphnode metastases) and estrogen and progesteron receptors were determined. A strong sinushistiocytosis and T-cellreaction could be verified mainly in metastases in free lymphnodes. The steroid receptor content does not correlate with histological parameters.

Breast Neoplasms↗

PubMed1981

[Value of beta-HCG blood levels in patients with malignant tumors of the testis].

In 24 of 43 patients (56%) with malignant germ cell tumors of the testis, the serum was positive for HCG prior to ablation of the testis. We give a detailed account of the course of HCG levels in the serum of 7 patients with seminoma of the testis. Positive serum-HCG-findings 8 to 10 days after semi-castration and prior to retroperitoneal lymphadenectomy indicate tumor metastases. In two thirds of our patients, we observed a correlation between regression of metastases under chemotherapy and the pattern of serum-HCG-levels.

Adult↗

PubMed1981

The endocrinology of testicular germinal cell tumors.

Oestradiol (Oe2), testosterone (T), lutenizing hormone (LH), follicle stimulating hormone (FSH), beta-human chorionic gonadotrophin (beta-hCG) and alpha-1 foetoprotein (AFP) were measured in blood samples taken from 63 patients with testicular tumours. In patients without tumour recurrence (n=31) AFP, Oe2 and T were within the normal range, beta-hCG was negative, LH levels were marginally elevated and FSH concentrations were significantly elevated. In patients with tumor recurrence (n=32) Oe2 was significantly elevated, whereas the T levels varied considerably and were therefore statistically not different from the patients without tumour recurrence. The beta-hCG positive subgroup of the recurrence group, however, demonstrated significantly elevated T levels. T levels were highest in patients with 51 to 500 U beta-hCG/1. On hand T was normal or even low normal in beta-hCG negative -AFP positive patients. In all subgroups decreasing FSH levels and decreasing LH responses to LRH were among the earliest signs of tumour recurrence. The observations suggest that moderate hCG levels are able to stimulate testicular T production, whereas high levels no longer increase T serum concentrations. Increased conversion rates form steroid precursors to oestradiol seem to be a feature of beta-hCG positive as well as beta-hCG negative testicular tumours.

Choriocarcinoma↗

PubMed1981