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The partnership the insulin-like growth factor (IGF) in women with polycystic ovary syndrome (PCOS) is characterized by mechanisms underlying alterations in the GH/IGF-1, axis. In the pathogenesis exist a synergism markedly enhanced between IGF-1 and insulin, and IGF-1 with LH to increase androgen production, causing a reduced IGFBPs and SHBG production, the resulting hyperandrogenism, within and outside the ovary, may inhibitor follicular maturation and the biosynthesis of estrogen. At the present, the data suggests up to date paracrine, autocrine as well as endocrine actions in the ovary in normal conditions and the lost of this homeostasis can be followed by neuro-endocrine.

The pituitary hormones prolactin and growth hormone are structurally related. Both hormones exist in the circulation in several molecular forms, differing in aminoacid sequences, posttranslational modifications and fragments produced by proteolytic cleavage. Heterogencity may produce a diversity of inmunological and biological actions. It has been suggested that each of this forms may be a isohormone with a different physiological role. The predominance of one of them in serun could account for the complex and often contradictory actions of the hormones. In addition receptors also have structural homology and so the possibility exist that these hormones share binding affinity to the receptors and can produce endocrinological problems in some special conditions.

Present study was designed to test that insulin resistance due to hyperinsulinism contribute to the clinical features of polycystic ovarian syndrome (POS). We studied 15 women wit POS who received Metformin 400 mg b.i.d during six months; blood levels of estradiol, testosterone (T), sexual hormone binding globulin (SHBG), insulin like growth factor-I (IGF-I) were determined. In response to treatment women exhibited decrement in serum levels of T as well as an increment, no significative, in both SHBG and IGF-I. Most of the patients showed reduction in body mass index and presented restoration of menstrual cycles. It is concluded that Metformin treatment exerts some metabolic effect which in turn induces some clinical improvement.

It is known that protein hormones circulate as different molecular forms and the relative proportion of these isoforms changes according to endocrine milieu. In particular gonadotropins, both LH and FSH, isoforms suffer variations related to the estrogen levels; thus sera obstained from menopausal women show a predominance of larger molecular forms which are considered as having lesser biological activity and the administration of estrogen replacement therapy is followed by the appearance of intermediate molecular forms possessing higher biological activity. This chormatographic pattern with predominance of intermediate isoforms is typical at midcycle in sera from normal women at the periovulatory stage. Present study showed that sera obtained from anovulatory women, such as patients with polycystic ovaries a predominance of larger and smaller molecular weight isoforms, exhibiting a chromatographic pattern different from that observed in normal women. It is speculate that there is some imbalance between the ovarian steroid synthesis and gonadotropin production in the stage of tertiary structural conformation.

Prolactin is a hormone involved in a variety of physiological processes in male and female of several vertebrates species. In mammalian included the human, it has been suggested that prolactin plays a role in immunoregulatory mechanism. There are some evidence in the sense that exists a notable bidirectional interaction between prolactin and the immune systems. This finding has stimulated the research on this area. Prolactin has stimulative effects on the lymphocytes and on the immune responses, and the cytokines production changes the prolactin concentration, so modifying its biological action. These reciprocal effects involve the presence of specific receptors. The prolactin receptors have been demonstrated on lymphocytes and other accessory cells. This review tries to summarize the interaction between immune and neuroendocrine systems and the importance of neuroimmune endocrinologic study.

Life expectancy in women has nearly reached 80 yr old, therefore the postmenopausal period is considered very important, particularly regarding the benefits of hormone replacement therapy. At the present there are several therapeutic options in order to protect against the long term complications resulting from chronic hypoestrogenism and avoiding some of the side effects associated with estrogens medication, tibolone is a synthetic steroid possessing mild estrogenic effect and some progestagenic and androgenic actions; moreover this steroid does not require to be converted to estradiol. We studied the effect of administering tibolone 2.5 mg daily orally during six months to 11 postmenopausal women in order to analyze any changes on several biochemical markers. Estradiol concentrations were not modified although FSH, total cholesterol, low density lipoproteins and triglycerides levels decreased. Collaterally there was observed an increment in high density lipoproteins and sexual hormone binding globulin. It is concluded that tibolone exerts its effect directly on specific receptor tissues without being converted to estradiol so that this finding may help to understand some of the clinical effects, particularly upon mammary gland, endometrium and body weight.

Sex hormone binding globulin (SHBG) is a glycoprotein that transports mainly androgens and estrogens regulating the amount of free and bound hormone which in turn plays a role in the metabolic balance. It is also known that estrogens increase the hepatic production of SHBG which circulates in various molecular forms containing different amounts of sialic acid as the main component of carbohydrates. In the present work we studied physiological variations of molecular forms of SHBG during the normal menstrual cycle and the menopause. During the follicular phase the form 54 KD was the predominant variant, in the periovulatory period was isomers 90 KD, and during the luteal phase corresponded to both 54 and 90 KD. In the menopause dimeric form of 90 KD corresponded to the major proportion and was present a higher molecular forms of 115-135 KD. Following estrogen therapy the chromatographic profile changed as to that observed during the menstrual cycle. Important changes in the proportion of sialic acid were observed in each of the phases of menstrual cycle and following estrogen replacement. And increase in the amount of sialic acid corresponded to higher estrogen concentrations. It is concluded that SHBG concentrations varies during the menstrual cycle according the estrogen levels which in addition regulates the proportion of molecular forms and sialic acid containt.

Although the embryo has a genetic program of its own development in order that development and embryonic differentiation take place, as well as normal gestation, a series of coordinated interactions between embryo and the mother, should be established; which are mediated by chemical messengers, autocrine, paracrine and endocrine. In this study, hormonal participation and regulating factors of implantation, and the feto-placental unit development, are analyzed.

The objective was to measure gastrin (G) levels in maternal and neonatal sera as well as in amniotic fluid in patients with fetal distress and a control group. Twenty-five patients with term pregnancies were assigned to the following two groups: fifteen with acute fetal distress and ten with previous cesarean section. Maternal and neonatal blood and amniotic fluid samples were taken at the time of delivery. Differences between groups were calculated with non-parametric Mann Whitneys' U test. A significant difference (p0.001) between G levels in amniotic fluid of fetal distress and those of the control group was found. In conclusion, serum G levels can be used as another predictor of fetal distress, although further studies must be performed before it can be used as a clinical tool.

It is known that hypophysial gonadotropins circulate in different molecular forms which are provided with different biological activity and that the proportion of such varieties keep a relation with the concentrations of estrogens in circulation. In physiological menopause predominate the great molecular forms which have a lesser biological activity and when estrogens are administrated a change is produced to smaller molecular forms. The present study tries to determine if in cases of ovarian insufficiency of long duration as in precocious menopause and the syndrome of refractory ovary the chromatographic conduct of gonadotropin is similar. Six patients with precocious menopause, and three with the syndrome of refractory ovary, were studied, in order to make a comparison of chromatographic pattern of FSF and LH in serum, with the one found in women with normal ovarian function and with physiologic menopause. The chromatographic analysis was done by filtration in gel of the serum and the subsequent determination of LH and FSH by RIA of double antibody. It was found that the chromatographic pattern of patients with ovarian insufficiency of long duration, characteristically presents larger molecular forms, specially in the refractory ovary syndrome with a greater alteration in the profile of LH. With base on these results it is concluded that the duration of ovarian insufficiency determine the type of molecular form, predominant, of gonadotropins. Also it is suggested that for the syndrome of refractory ovary, the greater heterogenicity of gonadotropins may explain part of physiopathogeny.

We studied 51 patients aged 20-35 years, with overweight or obesity evaluated by the body mass index (BMI = weight height2) when it was higher than 25 (normal 20-25), and a control group of six women with the same age and normal BMI. In all patients waist and hip circumferences were measured, to calculate the waist/hip ratio (WHR). Also serum insulin was measured in basal conditions and as response to 75 g oral glucose load, taking samples at 30, 60, 90, 120 and 180 minutes after. The test were performed 3 to 6 days following a spontaneous or induced genital bleeding with progestin. The WHR showed a normal distribution with the greatest frequency at 0.87. The patients were classified with predominance of adiposity in the upper body segment, when the WHR was equal or more than 0.85, and with adipose predominance in the lower body segment when it was equal or less than 0.84. The average insulin values in response to oral glucose load of patients with upper body segment obesity were significantly higher (Mann-Whitney's U = 0, p less than 0.02) than the corresponding cases with lower body segment obesity. Besides, there was a significant correlation between WHR and serum insulin values at 30 minutes after the oral glucose load (Pearson's r = 0.331, p less than 0.02). These results suggest a relation between the distribution of adiposity and insulin values, which were higher in patients with adipose predominance in the upper body segment.

In accordance with the lipophilic properties that are presented by steroidal molecules and the easy of their diffusion and ultrafiltration across serum to saliva, a competitive immunoenzymatic method based on the solid phase system (ELISA) is here in described, it aims to evaluate 17B oestradiol during menstrual cycle using saliva as the biological fluid. In order to apply this competitive system, the requirements are: as antigen 17B oestradiol immobilized on a solid phase, anti 17B oestradiol sheep serum, (1er. Ab) rabbit-globulin anti sheep serum (2o. Ab). The latter when it's conjugated to an enzyme will reveal and will evaluate the presence of 17B oestradiol-antibody reaction. This ELISA method offers acceptable results within a quality control program, indicating with respect to sensibility, a minimum detection level of 2.5 pg/ml. The specificity, which depends on the antibody used and its interaction with the structurally related steroids was not significative with oestrone (1.32%) and oestradiol, (2.46%). The recovery of 17B E2 was adequate (90-95%). In the standard curve the interassay coefficient of variation ranged between 3.0-4.8%; in the saliva samples, the intra assay and inter assay coefficient of variation were 7.2-9.4 and 4.8-12.1% respectively. With respect to the biological fluid used, we can say that saliva is one of the most accessible fluids in the human body and it can be obtained daily without problem. One additional advantage is that 17B E2 values showed excellent correlation with the menstrual cycle phases. So, because the safety, low cost and simplicity we think this ELISA method appears to be very convenient in order to measure oestradiol in normal and pathological conditions.

In this paper are presented some chromatographic studies for partition of different molecular forms of prolactin (PRL), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in infertile women. Serum from three patients with prolactinoma and six with premature ovarian failure were fractionated in Sephadex G-100, and eighty fractions were collected, where PRL or FSH/LH were measured by radioimmunoassay, according with each case. Patients with prolactinoma showed two different chromatographic patterns for PRL. Two women with secondary amenorrhea and galactorrhea showed predominance of "little" PRL. In contrast, the patients with primary amenorrhea and galactorrhea showed only "big" PRL and "big-big" PRL. Among the patients with premature ovarian failure, two had chromosomal mosaicism, two had refractory ovarian syndrome and the other two had idiopathic premature ovarian failure. In these patients were found the presence of several molecular forms of FSH and LH, with different chromatographic profiles to those observed in normal young women and postmenopausal women. These results are indicating the presence of several molecular forms of pituitary hormones in patients with prolactinoma and premature ovarian failure.