Changes in testicular weight and serum gonadotropin and testosterone levels before, during, and after birth in the perinatal rat.

Changes in serum and pituitary LH and FSH concentrations have been measured in the newborn male rat before, during, and up to 24 h after birth. A sudden and transient increase of serum and pituitary gonadotropins is observed at birth, which is followed by a rapid increase of absolute and relative testicular weights between 2--12 h (P less than 0.0001) and by a transient increase of serum testosterone between 0 h in utero (810 +/- 26 pg/ml) and 2 h (2820 +/- 318 pg/ml; P less than 0.0001). Similarly, premature newborn rats obtained by cesarian delivery on day 20 of gestation also exhibited an increase in testicular weight between 0--6 h and an increase in serum testosterone levels between 0 h (730 +/- 170 pg/ml) and 2 h (3400 +/- 300 pg/ml; P less than 0.001) with only a slight increase in serum LH. These results show that the hypophyseo-testicular axis of the rats is stimulated at the moment of birth. The factors responsible for this stimulation are discussed. This transient testicular crisis occurring at birth could affect the process of masculinization of the central nervous system of the rat.

Testosterone secretion by foetal rat testes in vitro.

Testosterone secretion by foetal rat testes (13 1/2-21 1/2 days of gestation) explanted for 3 days in a synthetic medium was measured every 24 h by radioimmunoassay. During the first day of explantation, the foetal testis produced, respectively, 1013 +/- 132, 8734 +/- 1118, 9179 +/- 2185 and 3886 +/- 309 (S.E.M.) pg/testis when explanted at 14 1/2, 16 1/2, 18 1/2 and 21 1/2 days respectively. Testosterone production by 13 1/2-day-old testes was not detectable on the first day of culture, but appeared on subsequent days. Daily testosterone secretion increased on the 2nd and 3rd days of culture in 14 1/2-day-old testes and decreased in older stages. These results suggest that the functional differentiation of the testis is independent of stimulatory factors like gonadotrophins. Dibutyryl cyclic AMP was found to stimulate testosterone production significantly from 14 1/2 days of gestation onwards.

Relationships between plasma progesterone levels and testicular testosterone production in the rat fetus: effects of maternal ovariectomy.

The present study was performed to examine whether circulating progesterone regulates testicular testosterone production in the fetal rat. Progesterone levels in fetal plasma were found to increase from day 14.5 to day 16.5; thereafter they reached a plateau between days 16.5 and 18.5 (80 nmol/l) and decreased threefold between days 18.5 and 21.5. The addition of progesterone, within the range of normal plasma concentrations, induced a dose-dependent increase in testosterone produced in vitro by the testes on days 16.5 and 18.5 but not on day 20.5. However, in 18.5-day-old fetuses, individual plasma progesterone levels were not correlated with testicular testosterone production in vivo and in vitro. Furthermore, maternal bilateral ovariectomy induced a significant fall in plasma progesterone in 18.5-day-old fetuses; this was not associated with a reduction in plasma testosterone nor in testicular testosterone content, although the amount of testosterone secreted by the testis incubated in vitro was slightly but significantly reduced. It is concluded that circulating progesterone does not regulate testicular testosterone production in vivo although the testis may use plasma progesterone as a substrate. On day 18.5 after maternal ovariectomy, the decrease in plasma progesterone levels was similar in fetuses and mothers, suggesting that most fetal progesterone originates from maternal plasma.

Effects of androgen injections and decapitation on the pituitary-gonadal axis and genital tract of fetal rats at the end of gestation.

The relationships between LH activity in the plasma, testicular and plasma levels of testosterone and prostatic buds were examined on day 21 of gestation in control and experimental male fetal rats. Surgical hypophysectomy by decapitation of the fetus 3 days before death produced a reduction of LH activity in plasma and level of testosterone in the testes; the development of cranial prostatic buds was impaired although plasma levels of testosterone were unchanged. Injections of testosterone propionate (10 mg) on days 18, 19 and 20 of gestation had similar effects on testicular testosterone; this effect was not due to a direct inhibition of androgen synthesis by testosterone, but to a lowering of LH activity and suggests the existence of a feedback mechanism of testosterone on the fetal hypothalamo-pituitary axis.

Testicular inhibition of fetal Mullerian ducts in vitro: effect of dibutyryl cyclic AMP.

The effect of dibutyryl cyclic AMP (dibutyryl cAMP) on Mullerian ducts of 141/2-day-old rat fetuses in vitro was investigated. Dibutyryl cAMP was unable to produce the typical regression of Müllerian ducts which is observed in vivo in male fetuses and in vitro with Müllerian ducts in the presence of testes. Effects of dibutyryl cAMP and theophylline on regeneration of Müllerian ducts induced by fetal testes were also investigated, and it was found that 10(-3) dibutyryl cAMP added to the culture medium prevented the normal regression. Lower concentrations and theophyline (10(-3)M) were ineffective. An effect of lower doses of dibutyryl cAMP was obtained only when theophylline was also present. Because pretreatment of testes with dibutyryl cAMP did not prevent the inhibiting action of testes on Müllerian ducts, it is concluded that an interaction between dibutyryl cAMP and the inhibiting factor at the level of the target organs must be considered.

Acquisition of sensitivity to LH in relation to foetal development. Stimulation of cyclic AMP and testosterone production in the rat testis.

The ability of LH to stimulate, in vitro, adenylate cylcase activity and testosterone secretion was studied in foetal rat testes after prelabelling with [14C]adenine. As little as 0.1 ng/ml LH produced significant synthesis of cyclic AMP and testosterone secretion. Increase of cyclic AMP production was observed as early as 1 min after addition of LH (100 ng/ml), preceding the rise in testosterone synthesis and secretion. FSH and prolactin were not effective. LH-stimulation of cyclic AMP and testosterone production appeared concomitantly in rat foetal testes on day 15 of gestation and reached a maximum on day 18. Immature testes (14 days) developed functional receptors when cultured in a medium devoid of hormone. The results of the present study suggest that cyclic AMP mediates the effect of LH on steroidogenesis in foetal testes and that the differentiation of functional receptors occurs at the same time as the capacity for testosterone synthesis.

LH/hCG receptors and stimulation of testosterone biosynthesis in the rat testis: changes during foetal development in vivo and in vitro.

The development of gonadotropin receptors to LH/hCG in the foetal rat testis from 14 to 20 days of gestation was monitored by quantitative binding assays using [125I]hCG and compared to testosterone secretion under basal and stimulated conditions in vitro. Specific hCG binding was first detected on day 15. Thereafter the binding increased gradually with advancement in gestational age and correlated with LH-stimulated secretion of testosterone in vitro. On day 18 of gestation the KA was 0.82 x 10(10) M-1 and the binding capacity was 0.57 fmoles per testis. No binding was detectable in the female gonads at this age. The differentiation of hCG receptors obtained in vitro was very low, although it was sufficient to give a full response to LH with testosterone biosynthesis. The results of the present study suggest that functional receptors do not appear before the capacity to synthesize testosterone is expressed and that their appearance is not dependent on factors extrinsic to the testis. However, additional factors could be necessary for a full development of the receptors.

Cholesterol side-chain cleavage activity in rat fetal gonads: a limiting step for ovarian steroidogenesis.

The aim of this study was to examine the first step in steroidogenesis in male and female gonads of fetal rats. Pregnenolone production was measured by radioimmunoassay in organ culture, conversion of [3H]cholesterol to [3H]pregnenolone was evaluated in isolated mitochondria and cytochrome P-450scc was revealed by immunoblotting and immunocytochemical techniques. Our results clearly showed that in fetal testes (1) pregnenolone was produced in media where testes were cultured in the presence of trilostane and spironolactone, indicating an important metabolism of pregnenolone, (2) [3H]cholesterol was converted into [3H]pregnenolone in mitochondria, (3) cytochrome P-450scc was revealed in immunoblots with a molecular weight of 50,000, (4) cytochrome P-450scc was localized in Leydig cells from 15.5-day-old fetal testes onwards. With respect to fetal ovaries, we were unable to detect any scc activity, except after treatment with dibutyryl cyclic AMP. A lag period of 18 h was necessary to induce pregnenolone synthesis. However, the immunoperoxidase staining did not localize ovarian positive cells. Cytochrome P-450scc could be revealed in postnatal ovaries by immunoblotting and some interstitial positive cells were observed with immunostaining; the reaction was enhanced in luteinizing hormone-pretreated ovaries. These data indicate that (a) the cholesterol scc activity is present in fetal testes, (b) the conversion of cholesterol to pregnenolone is a limiting step for steroidogenesis in fetal ovaries. The inductive effect of the nucleotide on the enzyme suggests that the absence of gonadotrophic receptors in fetal female gonads could explain the lack of steroidogenesis before birth.(ABSTRACT TRUNCATED AT 250 WORDS)

Responsiveness of rat ovaries to dcAMP in the perinatal period: evidence for an inhibitory influence in vivo.

The progesterone production by rat ovaries from 18-day-old fetuses to 6-day-old neonates was measured in vitro in the presence of dibutyryl cAMP (dcAMP, 1 mM). A pronounced decline was observed at the end of fetal life. The 5 alpha-reductase activity did not seem sufficient to explain this decrease. Preculture of the ovaries for 48 h in the basal medium enhanced responsiveness to the nucleotide. Addition of spironolactone, an inhibitor of 17 alpha-hydroxylase to dcAMP did not modify this evolution. 3 beta-hydroxysteroid dehydrogenase activity, detectable in fetal ovaries in the absence of dcAMP was also increased after preculture. In the presence of spironolactone and trilostane, the pregnenolone production showed the same evolution as progesterone and was also enhanced after culture. These results suggest the existence of inhibitory factor(s) present in vivo at the end of fetal life.

Tiroiditis de Riedel, una entidad fácilmente confundible con carcinoma anaplásico tiroideo / Riedel's thyroiditis, an entity easily confused with anaplastic thyroid carcinoma

INTRODUCTION: Riedel´s thyroiditis is a thyroid inflammation with invasive fibrosis. CASE REPORT: Female 84 years old, studied by dysphagia to liquids and dysphonia, with cervical mass poorly demarcated and immobile. Computed Tomography (CT) (CT) showed tumor that diverted the trachea and esophagus compressed. Fine Needle Aspiration (FNA) obtained cells with atypia. Thyroidectomy was performed, appreciating a stony tumor which included the right recurrent laryngeal nerve. Given the high suspicion of thyroid malignancy tracheostomy it was performed. The pathology report as fibrosing Riedel thyroiditis. DISCUSSION: This is the less common type of chronic thyroiditis. Etiology is unknown. The normal thyroid parenchyma is replaced by fibrous connective tissue. Clinically usually a hard mass, fast growing, why is confused with thyroid carcinoma and Hashimoto's thyroiditis. It´ss more common in women and is usually bilateral. The CT or MRI (Magnetic Resonance Imaging) help assess the extent. Puncturing the mass could give us the diagnosis but is often difficult. Treatment to relieve symptoms or rule out malignancy is surgery. The prognosis is usually good. CONCLUSIONS: Riedel´s thyroiditis is an entity with histopathologic diagnosis essential

[Long-term outcome of paediatric lupus nephritis]. / Evolución a largo plazo de la nefritis lúpica de inicio en la edad pediátrica.

INTRODUCTION: Kidney is frequently affected in patients with systemic lupus erythematosus (SLE). It has been recently suggested that the renal outcome in this disease has improved with an earlier diagnosis and intensive specific treatment. Quite often, articles with paediatric patients lack a prolonged follow-up which could help to predict long term outcome. METHODS: This is a retrospective descriptive study based on the review of clinical records from patients with a diagnosis of lupus nephritis in a Paediatric Nephrology unit of a tertiary care centre, between 1987 and 2009. Patients were included with an age up to 18 at diagnosis. They were excluded if follow-up period was shorter than 3 months or if data lacked about it. It includes descriptive evolution of clinical parameters, kidney function, lupus activity as well as pathology and treatment. Several variables were tested for association with chronic kidney disease (CKD) in the last checkpoint. RESULTS: Data were obtained from 16 patients, 3 men and 13 women. Age at the beginning of SLE was 10.6 + or - 2.9 years and 12.6 + or - 3.5 years at debut of lupus nephritis. Biopsy was obtained in 14 of them, in 11 cases (78.6 %), 3 or less months following diagnosis. In 9 cases (64.3 per cent), biopsy showed WHO class IV, 3 cases, class III and 2 cases, class II. In the last control (10.7 + or - 6.7 years of follow-up), 7/16 (43.8 %) had developed CKD: 5 cases with proteinuria (one in nephrotic range), one in stage 2 and one patient in haemodialysis after renal graft loss. Among those with a follow-up longer than 10 years, 4/9 (44.4 %) of them showed some sign of renal disease: 3/9 with proteinuria, and the one needing haemodialysis. Most of the patients (15/16) received treatment with intravenous cyclophosphamide boluses in a variable number after diagnosis. Only a more intense proteinuria at 3 months, 1 year and 3 years of evolution was related to CKD in the last visit. CONCLUSIONS: We consider the long term evolution of our patients to have been very satisfactory. Although 44.4 % of them developed renal anomalies after 10 or more years, only one (11.1%) reached an end-stage renal disease. These patients presented a higher grade of proteinuria from the first visits.

[Musculoskeletal pain: a common initial sign of acute lymphoblastic leukaemia]. / Dolor musculoesquelético: una forma de inicio frecuente de leucemia linfoblástica aguda.

Musculoskeletal pain is a common complaint in paediatrics usually due to benign diseases. Nevertheless neoplasms, particularly acute leukaemia, must be considered in the differential diagnosis. During the last 9 months 4 of the 9 patients diagnosed with acute leukaemia at our hospital presented with a limp, arthralgias, lumbar or bony pain. We describe these cases and review the clinical and analytical parameters that help to differentiate benign pain from that associated with a malignant disease. The early detection of these processes may represent a significant improvement in their prognosis.

Control of testicular steroidogenesis in foetal rat: effect of decapitation on testosterone and plasma luteinizing hormone-like activity.

These studies were designed to investigate the regulation of testicular testosterone and the role of the hypophysis during the last 5 days of gestation in the rat. Plasma LH-like activity was measured by bioassay and testosterone by radioimmunoassay. In both sexes, plasma LH-like activity levels were low on days 17.5 and 18.5 (less than 0.10-0.26 ng/ml) and rose on day 19.5 (0.10-1.25 ng/ml). Thereafter the levels increased considerably and were significantly higher in females than in males: on day 21.5 they reached 0.44-2.42 ng/ml in males and 2.20-3.96 ng/ml in females. Plasma levels of testosterone were significantly higher in males than in females and were maximal on day 18.5 in males. Testicular content of testosterone reached maximum values on day 18.5 and remained constant thereafter. Foetal decapitation clearly reduced testicular production of testosterone and plasma LH-like activity only after day 19.5. A residual gonadotrophic activity was detected at all stages in decapitated foetuses from both sexes (less than 0.10-0.46 ng/ml). These results suggest that pituitary LH secretion and pituitary-testicular interrelationships are essentially established between day 19.5 and 20.5, and that the ageing testis becomes more dependent on gonadotrophic stimulation. The existence of an extrapituitary LH-like activity might indicate the presence of placental gonadotrophins.

Attempts for identification of a chorionic gonadotrophin-like bioactivity in the rat placenta which stimulates the testosterone secretion of the fetal testis in vitro.

The bioactivity of rat placental extracts was evaluated using a fetal rat testis testosterone (FRTT) bioassay. It is based on the measurement of the increase in testosterone secreted in vitro by testes from 18.5-day-old fetuses in response to the addition of placental extracts. Placentas obtained on days 11.5, 12.5, 13.5, 14.5, 15.5, 17.5 and 19.5 and homogenized with a Potter homogenizer (1 placenta per ml incubation medium), increased the secretion of testosterone by 460, 690, 500, 300, 220, 200 and 170%, respectively. These extracts showed a high proteolytic activity capable of suppressing the bioactivity of 0.8 ng/ml LH added prior to the extraction procedure. However, the bioactivity of the placental extracts did not increase after inhibiting placental proteases by the addition of benzamidine. Heat treatment did not decrease the bioactivity of placental extracts obtained without inhibition of proteases. Ultrafiltration of the placental extracts obtained with inhibition of the proteases showed that most of the bioactivity was dialyzable. The levels of bioactive material with molecular weights greater than 10,000 were very low (0.06 ng LH equivalent/placenta on day 12.5 and less than 0.02 ng LH equivalent/placenta on day 14.5). These results suggest that rat placental bioactivity as measured with the FRTT bioassay is due, for the most part, to steroid precursors of testosterone and, for a very small part, to an LH/chorionic gonadotrophin (CG)-like molecule. Furthermore, after day 14.5, the placental LH/CG-like bioactivity, if it exists, is synthesized in too low levels to be able to control the testicular activity in the rat fetus.

A sensitive bioassay for luteinizing hormone-like activity applied to systemic plasmas of foetal rats.

A sensitive bioassay for plasma LH-like activity has been developed by utilization of the testosterone response of foetal rat testes to gonadotrophic stimulation in vitro. The volume of plasma required for the assay and the target organ make the methods suitable for bioassays of circulating LH-like activity in foetal rat plasma. When applied to foetal plasmas, the method has shown that castration performed on day 19 of gestation induced 24 h later an increase in the LH-like activity of the plasma and that decapitation under the same conditions led to a decrease in this activity in male foetuses.

Testosterone, dihydrotestosterone and estradiol-17 beta levels in maternal and fetal plasma and in fetal testes in the rat.

In Sherman rats testosterone, dihydrotestosterone (DHT) and estradiol-17 beta levels were measured in maternal and fetal plasma of both sexes during the last 5 days of gestation and in the fetal testes from day 14.5 of pregnancy using celite microcolumn chromatography and radioimmunoassay. All the plasma testosterone concentrations in males were at least 4 times higher than in their female littermates. In male fetuses, levels of plasma testosterone were maximum on day 18.5 (mean = 1.42 ng/ml) and declined thereafter (mean = 0.85 ng/ml on day 21.5). In female fetuses and in mothers, levels were consistently very low (mean less than 0.2 ng/ml). Plasma DHT titers in fetal plasma of the two sexes and in maternal plasma were consistently minute. Plasma estradiol-17 beta levels in fetuses did not differ between sexes; they were higher than maternal levels; there was a prepartum increase both in fetuses and their mothers. Testicular testosterone content became detectable on day 15.5, increased to reach a peak on day 18.5 (mean = 2.3 ng/testis) and remained at this plateau throughout the end of gestation. Intratesticular DHT and estradiol-17 beta were in minute concentrations. From these data we conclude that, in fetal rat, (1) DHT in genital tract is entirely formed in situ during masculinization, (2) among the three plasma steroids assayed, only testosterone can play a determining role in sexual differentiation.