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Monduzzi Editore.

Prothymosin alpha (PTMA) is a small acidic protein abundantly and ubiquitously expressed in mammals and involved in different biological activities. Until now, its specific function in spermatogenesis has never been properly investigated. Recently, the isolation of a cDNA encoding for PTMA from the testis of the frog Rana esculenta has been reported: ptma transcript is highly expressed throughout the frog reproductive cycle, peaking in September/October, in concomitance with the germ cell maturation; it is specifically localized in the cytoplasm of primary and secondary spermatocytes and, at a lower level, in the interstitial compartment, in Leydig cells.In this article we support the involvement of PTMA in the meiotic phases of frog spermatogenesis. The expression of ptma mRNA increases in the testis of frogs treated with the antiandrogen cyproterone acetate, which blocks the II meiotic division and induces an increase in SPC cysts; on the contrary, it highly decreases in the testis of animals kept at 4 degrees C and treated with human corionic gonadotropin, in concomitance with the induced block of spermatogenesis and the disappearance of meiotic cells in the tubules. Furthermore, for the first time we have also evidenced by immunohistochemistry the expression of PTMA in the nuclei of secondary spermatocytes, spermatids, and spermatozoa, as well as in the cytoplasm of interstitial Leydig cells. Taken together our data suggest for an important role of PTMA in germ cell maturation and/or differentiation during R. esculenta spermatogenesis.

In the present study, to evaluate the role that sigma receptors play in the physiology of the pineal gland, we assessed the effects of the sigma receptor ligand (+)-N-allylnormetazocine on the gland activity during either the day or the night. As compared to saline, (+)-N-allylnormetazocine enhanced the physiological increases in both pineal N-acetyltransferase (NAT) activity and melatonin content at night, but it did not affect the biosynthetic activity of the gland during the day. Moreover, (+)-N-allylnormetazocine potentiated the enhancement of NAT activity and pineal melatonin content induced by isoproterenol administration during the day. The nocturnal stimulation of pineal NAT activity and melatonin levels by (+)-N-allylnormetazocine was prevented by pretreatment with rimcazole, a specific sigma receptor antagonist. These results demonstrate that sigma receptor activation by (+)-N-allylnormetazocine is not able, by itself, to stimulate pineal melatonin production, whereas it potentiates the biosynthetic activity of the pineal gland when this is stimulated noradrenergically.

When Mallory's trichrome stain is used, acinar nuclei of the Harderian gland of Rana esculenta display different affinities for the dye. Some of the orangiophilic nuclei show affinity for aniline blue (blue nuclei). In the Harderian gland of Rana esculenta their number and the intensity of staining with aniline blue may vary during the year. The affinity for aniline blue disappears following digestion of paraffin sections with RNAase, but not with DNAase or trypsin. Furthermore, in vitro incubation with [5, 6-3H]-Uridine shows a selective incorporation by the majority of blue nuclei. Therefore, the affinity for aniline blue is likely due to increased RNA synthesis. The increment of nuclear RNA shown by these methods is supported by the quantitative determination of total RNAs during the resumption (October) and enhancement (May) of secretory activity, when the percentage of blue nuclei of the acinar cells is at its highest levels of the year. The affinity of RNA-rich nuclei for aniline blue, while others are strictly orangiophil, is discussed on the basis of molecular structure of the dyes used in the staining mixture. Mallory's trichrome stain appears to be an useful tool for detecting changes in cell nuclear status.

The differential staining of nuclei by the use of the Mallory trichrome method was investigated in a variety of tissues of representative vertebrates. By this method nuclei stained orange or blue; erythrocyte nuclei stained red. Since the higher affinity for aniline blue is due to an increased RNA synthesis, it was possible to reveal not only the changing metabolic status of a cell type, as shown for instance in the liver parenchyma and other glandular tissues, and nervous tissue, but also in different cell populations in the same tissue, such as the spleen.

We measured the plasma concentrations of luteinizing hormone (LH), oestradiol (E2), progesterone (P), 17 alpha-hydroxy progesterone (17P), androstenediona (A) and testosterone (T) at oestrus and during the oestrous cycle for four consecutive cycles in a group of 15 normal sows. The results show that at oestrus the peak LH value was preceded, 24 hours earlier, by an E2 peak, and indicate that the LH rise begins when E2 concentrations reach their highest value. During diestrus, concentrations of LH and E2 were constantly low, P and 17P were characterized by lowest concentrations during the oestrous period which showed significant (p less than 0.001), progressive increases from the second day after the LH ovulatory peak, to reach their highest values after 8-14 days. The 17P decrease in proestrus precedes that of P.T and A concentrations showed a significant (p less than 0.001) increase 2 days before the LH ovulatory peak; high plasma concentrations of both androgens were maintained until the LH peak occurred. Measurements taken in consecutive cycles in the same animals showed a high reproducibility of the hormone concentrations examined, which showed similar patterns and values in each of the cycles studied. This high reproducibility suggests that these hormones have an important physiological role and may affect oestrous behaviour.

The Harderian gland in Rana esculenta has been studied during the annual cycle at the histological, histochemical and ultrastructural levels. The Harderian gland has an acinar structure and is the only orbital gland in anuran amphibia. It develops at the medial corner of the orbit from the conjunctival epithelium at the premetamorphic stage. In the adult the glandular secretion reaches a maximum during the months of July and August, drops in September and resumes slowly from October onwards. The secretion is seromucoid and the secretory granules are released into the acinar lumen, mainly by exocytosis. Porphyrins were not detected. No sexual dimorphism was observed in the glandular cells. The resumption of secretory activity in October and the enhancement of secretion in May are marked by the appearance of "blue nuclei" (Mallory stain) in a relatively high percentage of glandular cells. This unusual blue colour, using the Mallory stain (by which nuclei stain red), disappears after digestion of paraffin sections with RNAase, but not with DNAase and trypsin. The blue staining may, therefore, indicate an increased amount of nuclear RNA. The Harderian gland in the frog most probably serves to lubricate and moisten the eye in the absence of the lacrimal gland. However, the gland may also represent an immunoactive organ owing to the presence of numerous mast cells and plasma cells in the interacinar spaces.

The effect of adjuvant CMF (cyclophosphamide, methotrexate and 5-fluorouracil) and tamoxifen (TM) on endocrine function was studied in 120 women with stage I-II operable breast cancer. Sixty patients were premenopausal, of whom 25 were treated with CMF for 9 months, 25 received CMF for 9 months + TM for 2 years, started concurrently, and 10 TM alone for 2 years. In all groups treatment was started within 4 weeks from mastectomy. Sixty patients were postmenopausal and they were all treated with TM alone for 2 years. Plasma levels of estrone + estradiol -17 beta (E1 + E2), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (Prl), and testosterone (T) were determined in all patients before surgery and again at 3-month intervals from initiation of the adjuvant therapy. In ten patients of each treatment group FSH-LH and Prl-TSH release was determined following stimulation with releasing hormones. CMF and CMF + TM therapy resulted in amenorrhea in the majority of premenopausal patients with decrease of E1 + E2 and elevation of FSH-LH plasma concentration to levels of the post-menopausal. In premenopausal women treated with TM a marked increase of E1 + E2 was observed with unaltered FSH-LH plasma concentration. A significant fall of Prl was also present in these patients. In postmenopausal women and premenopausal patients with CMF-induced amenorrhea TM produced a marked fall of FSH-LH and a decrease of Prl plasma level. In no patients was plasma T affected by any of the treatment regimens.(ABSTRACT TRUNCATED AT 250 WORDS)

PER LA PRIMA VOLTA E' STATO DOSATO IL PROFILO DEGLI O. SESSUALI DELLA SCROFA DURANTE IL CICLO ESTRALE