Search results for "Progesterone."

Chapter 4 Cholesterol and steroid hormones: modulators of oxytocin receptor function

2002

The function and physiological regulation of the oxytocin-receptor system is strongly steroid-dependent. This is, unexpectedly, only partially reflected by the promoter sequences in the oxytocin receptor and favors the idea that posttranscriptional mechanisms may also play a significant role for the physiological regulation of the oxytocin-receptor system. Our data indicate that cholesterol acts as an allosteric modulator of the oxytocin receptor and stabilizes both membrane-associated and solubilized OT receptors in a high-affinity state for agonists and antagonists. Moreover, high-affinity OT receptors are 2-fold enriched in cholesterol-rich plasma membrane domains in HEK293 fibroblasts s…

O069. Menstrual cycle affects cortical excitability differently in females with migraine and in healthy controls: a new perspective by cross modal so…

2015

The sound-induced flash illusions (SIFI) represent a valid tool to explore multimodal perception and are critically dependent on visual and acoustic cortical excitability [1, 2]. In a previous study [3], we observed a significant reduction of illusions in migraine patients with respect to healthy controls, probably due to a condition of visual cortex hyperexcitability. Aim of the present study was to evaluate SIFI perceptions in healthy women and patients with menstrual migraine and to describe the effects of cyclical change of steroid hormones and cortical responsiveness.

Hysteroscopic and ultrasonographic evaluation of ulipristal acetate treatment for symptomatic myomas in premenopausal women: a prospective study

2020

Objective: This study aimed to analyze the effects of a six-month therapy with ulipristal acetate (UPA) on myoma size and endometrial thickness in premenopausal women. Material and methods: Seventy-four women undergoing conservative therapy with UPA were enrolled for this study. All women underwent transvaginal ultrasound evaluation to assess the endometrial thickness, and the number and size of myomas at the beginning and after six months. Hysteroscopy and biopsy were performed after six months, if necessary. Results: After six months of treatment, sonographic examination showed a statistically significant (p <.05) reduction of the size of the largest myoma (56.3 ± 5.1 vs. 31.7 ± 10.1 m…

Lack of binding of gestodene to estrogen receptor in human breast cancer tissue

1990

Competition studies with progesterone and estradiol receptors of human myometrial tissue as well as of mammary cancer tissue showed that gestodene bound with high affinity to the progesterone receptor, as did other synthetic and natural progestogens. However, gestodene did not bind to the estradiol receptor. The relative binding affinities of all tested synthetic and natural ligands showed no organ-specific differences and no differences between neoplastically transformed and normal tissues.

Progestogens reduce thromboxane production by cultured human endothelial cells.

2011

Objectives Progestogens have been poorly studied concerning their roles in endothelial physiology. Prostanoids are vasoactive compounds, such as thromboxane A2, a potent vasoconstrictor, and prostacyclin, a vasodilator. We examined the effects of two progestogens used clinically, progesterone and medroxyprogesterone acetate, on thromboxane A2 production by cultured human umbilical vein endothelial cells (HUVEC) and investigated the role of progesterone receptors and the enzymes involved in production of thromboxane A2 and prostacyclin. Methods Cells were exposed to 1‐100 nmol/l of either progesterone or medroxyprogesterone acetate, and thromboxane A2 production was measured in culture mediu…

Progestogens stimulate prostacyclin production by human endothelial cells.

2005

BACKGROUND: The effects of progestogens on endothelial physiology are poorly studied. Prostacyclin is a potent vasodilator synthesized by two isoforms of cyclooxygenase (COX) in endothelium. We examined the effects of two clinically used progestogens, progesterone and medroxyprogesterone acetate (MPA), on prostacyclin production by cultured human umbilical vein endothelial cells (HUVEC) and the possible role of progesterone receptors and both COX enzymes. METHODS: Cells were exposed to 1-100 nmol/l of either progesterone or MPA and prostacyclin production was measured in culture medium. RESULTS: Both progestogens significantly increased prostacyclin release in a time- and dose-dependent man…

Poly(adenosine diphosphate-ribose) polymerase in quail oviduct. Changes during estrogen and progesterone induction

1974

Abstract The activities of the following enzymes have been determined in nuclei of quail oviducts in response to exogenous stimulation of the birds with diethylstilbestrol, used as an estrogen analogue and progesterone: DNA dependent DNA polymerase, DNA dependent RNA polymerase I and II and poly(adenosine diphosphate-ribose) [=poly(ADP-Rib)] polymerase. During primary stimulation with the estrogen analogue the activities of the four DNA dependent polymerases increase to about the same degree. Upon withdrawal of the hormones the levels of the enzymes drop to values known from nuclei from unstimulated quail oviducts. The secondary stimulation with the estrogen analogue causes a significant in…

Regulation by oestrogens of tachykinin NK3 receptor expression in the rat uterus.

1997

The expression of the tachykinin NK3 receptor and its regulation by ovarian steroids were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) in uteri from ovariectomized rats. A single transcript corresponding to the 325-bp product expected for the tachykinin NK3 receptor was detected in uteri from olive oil-treated (control) ovariectomized rats. The level of tachykinin NK3 receptor mRNA in progesterone-treated animals was similar to that observed in uteri from control ones. Tachykinin NK3 receptor mRNA levels were significantly smaller in uteri from oestrogen-treated ovariectomized rats, with approximately a 32-fold decrease. These findings suggest that oestrogen, but not…

Autoimmune Progesterone Dermatitis: A Complex Case

2018

Estradiol, progesterone, 17-hydroxyprogesterone, androstenedione and CA125 in patients with ovarian carcinoma.

1992

Estradiol, progesterone, 17-hydroxyprogesterone, androstenedione and CA125 were assayed in 25 women (12 oophorectomized before entering the study) with ovarian carcinoma. The data from patients were ordered according to the presence or absence of the gonads. The patients with ovaries (Group A) showed significantly higher levels of estradiol (p less than 0.01), progesterone (p less than 0.01) and 17-hydroxyprogesterone (p less than 0.01) than controls. This difference was not observed between oophorectomized patients (Group B) and controls. CA125 levels were significantly higher in patients that in controls (p less than 0.001) irrespective of the ovarian status of the patients. Eleven patien…