Besides having a remarkable progestogenic effect an addition

Besides having a remarkable progestogenic effect, an additional characteristic of DRSP is its strong antimineralocorticoid effect and antiandrogenic action [11]. DRSP is characterized by an antimineralocorticoid effect that is stronger when compared to progesterone. The decreasing synthesis of progesterone during the perimenopausal years is seemingly related to the increasing prevalence of salt sensitivity and its adverse effect on blood pressure regulation [13]. In a multicenter, placebo-controlled trial in hypertensive postmenopausal women randomized to either DRSP/estradiol or placebo, there was a significant reduction in systolic and diastolic blood pressure in the DRSP/estradiol group compared with placebo, but no statistically differences in serum potassium across the entire, diabetic and non-diabetic study population [14]. In addition, the DRSP/estradiol combination effectively relieves menopausal symptoms, lowers body weight and improves the lipid pattern. Altogether, this can lead to potential benefits on cardiovascular risks [15], [16]. DRSP does not abolish the beneficial effects of estradiol on the cardiac microcirculation [17] and induces a reduction of the carotic artery intima-media thickness when DRSP/estradiol is used [18]. It was also found that DRSP/estradiol reduces the risk of ocular diseases and nasal obstruction in postmenopausal women [19]. There is not only a decrease of nasal air flow resistance, but also an improvement of olfactory function [20].
Nomegestrol acetate (NOMAC) NOMAC is a 19-norprogesterone derivative (Table 1); its structure is shown in Fig. 1c. The pattern of partial hormonal effects of NOMAC can be seen in Table 2. NOMAC reaches a peak plasma concentration at 2–3h regardless of the oral dose, and its bioavailability is about 65%. Most of the steroid is bound to plasma albumin; it does not bind to SHBG or CBG. The metabolites of NOMAC do not show relevant progestational activity. The steady-state of NOMAC is reached after 5 days, and its elimination Piceatannol receptor is about 50h. NOMAC is a very strong agonist for the progesterone receptor, and its antiestrogen activity is also strong. In addition, NOMAC has weak antiestrogenic activity and no activity at the glucocorticoid and mineralocorticoid receptors [21], [22].Clinically, NOMAC has been used as monotherapy in dosages of 2, 5 to 10mg for menstrual cycle bleeding disorders. NOMAC has been studied in HT in doses of 1.5 to 3.75mg combined with estradiol (1.0 or 2.5mg). Both combinations have favourable effects on lipid metabolism, and no change on other metabolic factors or hemostasis. Menopausal symptoms are well controlled [8]. Due to its potent antigonadotropic effect, NOMAC is also suitable for hormonal contraception [8], [22].
Conclusions The “newer” progestogens belong to different classes based on their structure (Table 1). For each of them the progestogenic, as well as the antiestrogenic action, is common (Table 2). The antiandrogenic effect is relevant for DNG and DRSP and minor for NOMAC. None of them have a glucocorticoid effect. DRSP is different due to its strong antimineralocortocoid action, and has a favourable effect on blood pressure. In addition, these progestogens do not interfere with the positive effect of estrogens on lipid and carbohydrate metabolism, do not augment hemostasis processes as monotherapy and avoid induction of abnormal proliferation of the endometrium in doses clinically tested. Therefore, all three progestogens appear to be suitable for treatment of menopausal women.
Introduction A pretreatment technique named porous membrane protected micro-solid-phase extraction (μ-SPE) was proposed by Basheer et al. in 2006 [1]. It is based on the packing of small amount of sorbent material in a sealed porous membrane envelope. Compared to other pretreatment techniques, the method has several advantages, such as preventing the loss and blockage of sorbents, reducing matrix effect, portable, durable, robust, easy to manipulate, time and cost saving, and so on. So far, μ-SPE has been widely used as extraction technique for analysis of numerous target compounds in environmental, food, and biological samples [2].