Expression of gonadotropin-releasing hormone (GnRH) receptor gene is altered by GnRH agonist desensitization in a manner similar to that of gonadotropin beta-subunit genes in normal and castrated rat pituitary.

It was previously established that the administration of a potent GnRH agonist such as triptorelin (D-Trp6-GnRH) induced desensitization of pituitary gonadotropic cells, resulting in decreased expression of gonadotropin beta-subunit genes and the suppression of LH and FSH synthesis and release. Binding of GnRH to the pituitary is also affected by agonist treatment. To examine the desensitizing effects of GnRH agonist on the expression of the pituitary GnRH receptor (GnRH-R) gene, male rats were given triptorelin (long-acting formulation, 300 micrograms/kg), and levels of GnRH-R messenger RNA (mRNA) were determined by Northern and dot blot hybridization to a 32P-labeled rat complementary DNA probe.

Effect of Decapeptyl (a GnRH analogue) and of transforming growth factor-alpha (TGF-alpha), in the presence of heparin, on the sulfatase activity of human breast cancer cells.

The effects of the polypeptide Decapeptyl (a gonadotropin-releasing hormone (GnRH) agonist analogue) and of transforming growth factor-alpha (TGF-alpha), on estrone sulfate-sulfatase activities in the homogenates of various breast cancer cell lines were studied in the presence of heparin. In hormone-dependent MCF-7 breast cancer cells, Decapeptyl can inhibit sulfatase activity, and this effect is significantly augmented in the presence of heparin. In the other hormone-dependent T-47D breast cancer cell line, the decrease of sulfatase activity was only significant when Decapeptyl was associated with heparin.

Administration of a gonadotropin-releasing hormone agonist during pregnancy: follow-up of 28 pregnancies exposed to triptoreline.

Objective: To evaluate the teratogenic or fetal risk of a long-acting GnRH agonist (GnRH-a) triptoreline acetate (Decapeptyl; Ipsen-Biotech, Inc., Paris, France), inadvertently administrated in the first weeks of pregnancy.

Design: Prospective follow-up of exposed pregnancies and case reports.

[Treatment of central precocious puberty with sustained-release triptorelin].

Central precocious puberty is defined as the appearance of morphological and biological changes induced by the early maturation of the hypothalamic-pituitary-gonadal system before eight years of age in girls and ten years of age in boys. This early onset of the gonadotropin-releasing hormone pulse generator activation leads to secretion of gonadal steroids and therefore to the development of secondary sexual characteristics. The aim of medical treatment is to suppress the secretion of sex hormones.

[Treatment of acromegaly with a new slow release somatostatin analog, lanreotide].

Treatment of Acromegaly has been improved by the development of the somatostatin analogs characterized by an increased specificity and longer duration of action. One of these analogs-Lanreotide- (Somatuline) is supplied under a slow release formulation and does not require several daily injections like other analogs presently available. The clinical pharmacodynamic studies that have been conducted in healthy and acromegalic patients show that the i.

Effect of triptorelin (Decapeptyl) combined with heparin on estradiol levels in MCF-7 mammary cancer cells after incubation with estrone sulfate.

The effects of triptorelin (Decapeptyl) and heparin, alone or in combination, on the intracellular concentration of estradiol (E2) after incubation of estrone sulfate (E1S) with the MCF-7 mammary cancer cells was investigated. Although heparin (10 mg/l culture medium) or Decapeptyl (5 x 10(-7) or 5 x 10(-5) mol/l) did not affect the levels of radioactive E2 after incubation with [3H]E1S, the combination of Decapeptyl and heparin significantly decreased the radioactive uptake and the intracellular concentrations of [3H]E2. In the absence of Decapeptyl and heparin incubations with E1S, the resulting E2 concentration (in nmol/kg DNA +/- SD) was 558 +/- 44; after heparin (10 mg/l) plus Decapeptyl (5 x 10(-7) or 5 x 10(-5) mol/l) the values were 389 +/- 55 and 165 +/- 18, respectively.

Non-responsiveness of serum gonadotropins and testosterone to pulsatile GnRH in hemochromatosis suggesting a pituitary defect.

We investigated the potential pituitary origin of gonadal insufficiency in hemochromatosis. Gonadotropin secretion was studied in seven patients with hemochromatosis and hypogonadism, before and after chronic pulsatile GnRH therapy. Pulsatile LH secretion was studied before (sampling every 10 min for 6 h) and after 15-30 days of chronic pulsatile GnRH therapy (10-12 micrograms per pulse).

[Diabetic thoracoabdominal neuropathy. Clinical and electrophysiological study with evaluation of the autonomic nervous system].

We report on eight patients with diabetic thoracoabdominal neuropathy in whom careful evaluation of peripheral and autonomic nervous system function was performed. All patients had non insulin-dependent diabetes mellitus of 10.5 +/- 6.

Testicular tumors in congenital adrenal hyperplasia: steroid measurements from adrenal and spermatic veins.

The present study reports the case of a 25-yr-old man with congenital adrenal hyperplasia due to 21-hydroxylase deficiency in whom bilateral testicular tumors did not regress after suppressive treatment with dexamethasone. Catheterization of left testicular and adrenal veins confirmed the enzyme deficiency in the gonadal lesions. The presence of specific 11 beta-hydroxylated steroids (11 beta-hydroxyandrostenedione, 21-deoxycortisol, and 21-deoxycorticosterone) in the gonadal vein demonstrated the adrenal nature of the testicular tumor.

Altered balance between thyrotropin-releasing hormone and dopamine in prolactinomas and other pituitary tumors compared to normal pituitaries.

We measured TRH and dopamine (DA) concentrations in prolactinomas and other pituitary tumors in order to further understand the roles of these two factors in the hormone hypersecretion and growth of these tumors. The mean TRH concentration (by RIA) in 16 prolactinomas was 247 +/- 92 (+/- SE) fmol/mg cell protein (range, 10-1297), near that found in normal pituitary tissue. The prolactinoma TRH content did not correlate with the patient's tumor size or plasma PRL level.

Receptors and neurohormones in human pituitary adenomas.

In order to go further into the pathogenesis of human pituitary adenomas, we studied receptors for neurohormones (thyroliberin, TRH; dopamine, DA; somatostatin, SRIH), for estradiol and epidermal growth factor (EGF) thought to influence hormone secretion and/or cell growth. The following results were obtained: (1) the receptors listed above, with the exception of EGF receptors in the adenomas, are present in normal pituitary tissue and in prolactin (PRL)- and growth hormone (GH)-secreting adenomas; (2) they are functional and their affinities are not different in normal or tumoral tissues; (3) their density is variable and depends on the type of secreting adenoma (GH or PRL), the size of the tumor and the plasma level of the hormone which is secreted, and (4) in nonsecreting adenomas, only TRH receptors are found with characteristics identical to those observed in secreting adenomas. We also showed that TRH is contained in normal and tumoral pituitary tissues.

[Release of thyrotropin releasing hormone (TRH) from human prolactin-secreting pituitary adenoma cells. Modulation by dopamine].

We found, by radioimmunoassay, that thyrotropin-releasing-hormone (TRH) was present in human prolactin (PRL)-secreting adenomas (mean: 89 +/- 45 (SEM) fmol/mg proteins) and was released by perifused adenomatous cells at levels varying from 5 to 60 fmol/10(6) cell/2 min. TRH release was increased in the presence of dopamine (DA) 10(-6) M but was not modified by the presence of somatostatin (SRIH) 10(-6) M.

[Innocuousness of the limited reuse of injection materials by insulin-dependent diabetics].

A survey was conducted in 120 insulin-dependent diabetics to determine their routine daily procedure for insulin injection and the possible reuse of the material employed. Aseptic precautions were usually sufficient, half of the diabetic patients (51.6%) conforming with the overall rules for hygiene generally recommended.