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International audience; The action of neuropeptide Y (NPY) and gonadotropin releasing hormone (s-GnRH) have been compared on the release of gonadotropin (GtH) by perifused rainbow trout pituitary glands sampled from freshly ovulated female rainbow trout. We have already demonstrated that NPY stimulated the secretion of GtH in vitro. The pituitary responses to s-GnRH and NPY were similar either after repeated 10 min infusions or a one hour prolonged application. In both cases, after the first application, the pituitary did not responded to subsequent secretagogues stimulations, and appeared to be desensitized. The stimulatory action of s-GnRH was partly inhibited (60%) by LH-RH antagonist (DpGlu1, DPhe2, DTrp3-6) LH-RH, which completely inhibited the response to NPY in perifused pituitary glands sampled from freshly ovulated females, but did not modify the response of pituitaries taken from vitellogenic animals in which NPY induced a transient inhibition of the GtH secretion. These results may indicate that the mode of action of NPY would differ between vitellogenic and matured animals. NPY also stimulated the GtH secretion from perifused pituitary dispersed cells prepared from pituitaries taken from freshly ovulated rainbow trout, indicating that NPY may act directly on the pituitary gonadotropic cells to stimulate GtH secretion.

International audience; Juvenile rainbow trout received gonadotropic hormone (GtH) treatment to investigate the response of the immature gonad and its effect on the onset of rising pituitary GtH levels, an early sign of initiation of sexual maturation in the teleost fishes. Brief exposure to GtH evoked increases in plasma androgens and significantly increased pituitary GtH in males; the accumulation of pituitary GtH was not observed in female trout which showed significant but smaller increases in plasma androgen resulting from GtH administration. There was no evidence of gonadal negative feedback in intact immature fish since pituitary GtH and plasma androgens remained at basal levels in castrate juvenile trout. Since the castrate male trout failed to respond to GtH injections, the data suggest that the immature gonad produces a steroid capable of triggering pituitary GtH production by hypothalmo-pituitary feedback in males.

International audience; Changes in the maturational gonadotropin (c‐GtH) levels during 24 h in carp males, as a result of the presence or absence of other carp specimens, were investigated. Carp males were cannulated to ventral aortae. Gonadotropin levels were radioimmunologically determined. It has been found that in males two peaks of c‐GtH occur strictly in 2 periods during the day in which spawning takes place under natural conditions (early morning and late evening). Being in contact or not with another male or hypophysed female did not affect circadian changes in c‐GtH levels in investigated males.

International audience; A testicular feed back on the hypothalamo-pituitary system was studied in male rainbow trout (Salmo gairdneri) after bilateral castration and steroid or testicular supplementation. Experiments were carried out at various periods of the spermatogenetic cycle ; in March-April (resting stage), June (initiation of spermatogenesis), October (end of spermatogenesis and before spermiation), and December (running stage). In March and April, plasma t-GTH is low in intact males (< 2 ng/mi) and castration induced a threefold rise of GTH. Testosterone (T) given by a silastic capsule inserted in the body cavity of the castrate did not change plasma t-GTH in comparison with the intact control. When T is given in the same manner in intact males GTH is significantly increased. In June, a significant t-GTH rise was observed after castration (P < 0.05), this rise was prevented by injection of T and estradiol ()2.E When 2E and T were given to intact males plasma t-GTH was significantly decreased. In October plasma t-GTH was high (13 ng/ml) and was not modified by castration ; injected T or E2 had no effects on plasma t-GTH either in intacts or castrates. In December, a sevenfold increase of t-GTH is observed after castration. This was partly suppressed by intraperitoneal injection of T and E2 and declined after stereotaxic implantation of 11-ketotestosterone into the pituitary. It was not significantly suppressed by intraperitoneal injection of testicular extracts. It is suggested that at this period steroids are the main gonadal factors involved in the feed back at the hypothalamo-pituitary system level.

International audience; Une technique d'hypophysectomie par voie operculaire particulièrement simple et rapide, est décrite chez le Guppy Poecalia reticulata. La pénicilline administrée pendant la cicatrisation diminue la mortalité postoperatoire.A quick easy surgical technique of hypophysectomy using opercular approach is described in the Guppy Poecilia reticulata. The addition of penicillin to the water during the healing phase reduces poset-operative lethality.

The lactogenic properties of extracts of the pituitary glands of salmon and trout were evaluated by using the organ culture technique with rabbit mammary explants. Crude extracts and fractions obtained after chromatography on Ultrogel and selected for their capacity to compete with ovine prolactin in a rabbit mammary gland radioreceptor assay were added to the culture medium. The criteria of lactogenesis were lactose synthetase activity, casein synthesis, measurements of the concentration of casein messenger RNA and the histology of mammary glands. All these tests led to the conclusion that salmon and trout pituitary glands contain a prolactin-like principle capable of initiating milk synthesis in the rabbit mammary cell.

Le cycle reproducteur des poissons est sous la dépendance de l'hypophyse qui élabore et secrète les hormones gonadotropes. Ces hormones interviennent lors du déroulement de la gamétogenèse et sont produites activement pendant la maturation ovocytaire puis l'ovulation. La technique d'induction de ponte dite technique d'hypophysation consiste en un apport exogène d'hormone gonadotrope par injection d'hypophyses pour provoquer le déroulement de phases du cycle sexuel qui ne se produisent pas spontanément en condition de captivité comme l'ovulation.

International audience; To study the regulation of gonadotropin secretion in rainbow trout in vitro, a method for preparing primary cultures of dispersed pituitary cells is described. Cells were dispersed by collagenase 0.1% in Hank's saline solution for 20 hr at 12 degrees and a high yield of viable cells was obtained. Attempts to improve cell functioning were made by varying culture conditions (density of cells initially plated, age of the culture). Cell functioning was assessed by their ability to respond to increasing doses of mammalian and salmon GnRH. Pituitaries were collected from spermiating males whose pituitaries are known to be sensitive to mammalian GnRH in vivo. Using 96-well plates, optimal conditions for good biological activity, are initial plating with 6.2 X 10(4) cells, incubation with GnRH for 24 hr on the third day after plating. In these conditions mammalian analog and salmon GnRH induced an increase in GtH release for doses ranging from 10(-9) to 10(-6) M. The GtH released during the GnRH incubation period does not decrease the sensitivity of the system since addition of 20 ng of GtH at the beginning of incubation does not modify the response profile.

International audience; The efficiency of different hormonal treatments to induce ovulation of carp at low temperatures (13–15°C) was tested. “Priming” with a low dose (0.6 mg/kg) of carp pituitary extract was found necessary for a subsequent successful treatment with 17α-hydroxy-20β-dihydroprogesterone (17α-20β P) (2 mg/kg) 1 day later. The eggs produced by this method showed satisfactory fertilization (75–96%) and hatching success (70%).On the other hand, normal hypophysation (5.4 mg/kg) following priming resulted only in partial ovulation and oocyte resorption at this temperature. Priming was shown to increase the gonadotropin level in plasma from about 2 to 35 ng/ml and to induce germinal vesicle migration toward the periphery of oocytes. Neither 17α-20β P nor desoxycorticosterone alone or in association gave any positive result in the absence of a preliminary priming.

Le cycle reproducteur des poissons est sous la dependance de l'hypophyse qui elabore et secrete les hormones gonadotropes. Ces hormones interviennent lors du deroulement de la gametogenese et sont produites activement pendant la maturation ovocytaire puis l'ovulation. La technique d'induction de ponte dite technique d'hypophysation consiste en un apport exogene d'hormone gonadotrope par injection d'hypophyses pour provoquer le deroulement de phases du cycle sexuel qui ne se produisent pas spontanement en condition de captivite comme l'ovulation.

A CO2 laser ray has been used in order to destroy in situ the pictuary gland of a welsh pony. Animal preparation, surgical procedure, post operative treatment and following of operation are exposed., L'utilisation d'un rayon laser au CO2 a été mise à profit pour détruire in situ l'hypophyse d'un poney Welsh. La préparation de l’animal, les différents temps de l'intervention, les soins post-opératoires et les suites de l'opération sont exposés., Locatelli A. Première destruction in situ de l’hypophyse du cheval . In: Bulletin de l'Académie Vétérinaire de France tome 137 n°1, 1984. pp. 171-176.

International audience; The effect of implanting an extra pituitary containing large amounts of gonadotropic hormone (GtH), combined or not with a luteinizing hormone releasing-hormone analogue (LHRHa) treatment, on GtH levels and gonadal development was investigated in juvenile host fish. The extrapituitaries were collected from mature spermiating fish or from immature fish treated with testosterone. In recipient males and females circulating plasma GtH levels increased following transplantation of both types of pituitaries. Elevated GtH levels presumably triggered steroid synthesis by the immature male gonad since pituitary GtH content was observed to accumulate in recipient males and not in females. However, the potency of the two kinds of pituitaries seemed different since spermatogenesis was stimulated only in some recipient males bearing a mature adult pituitary. This divergence could be due to a different sensitivity to endogenous gonadotropin-releasing hormone (GnRH). Only mature extrapituitaries might be highly sensitive to GnRH, as suggested by results obtained in juvenile host fish after LHRHa treatment. At the end of the 6-week experimental period, this LHRHa treatment stimulated spermatogenesis and induced a significant increase in pituitary GtH content only in juvenile hosts transplanted with a mature pituitary. Such a result was not observed in juvenile hosts submitted to a LHRHa treatment combined or not with the transplantation of juvenile testosterone-treated pituitary. However, previous works have shown that pituitaries collected from immature testosterone-treated fish are sensitive to GnRH. In the present experiment, the amount of GnRH-induced GtH release might have been too low to initiate spermatogenesis during the 6-week experimental period.

Reproductive physiology in cichlid fishes, with particular reference to Tilapia and Sarotherodon

Séance du 27 mai 1979 à Brest; Using radioimmunoassays, plasma levels of carp gonadotropin (c-GTH) and oestradiol-17beta (E2) are measured every day in Carp, during induced spawning (water temperature = 15 °C). Ten Carps injected twice intraperitonealy with a total extract of Carp hypophysis (0,6 mg/kg BW at J0 and 5,4 mg/kg BW at J1) are compared to a lot receiving only saline solution. No evolution is detected in that last group when in the experimental one E2 level increases with exogenous c-GTH (see table). Even if E2 levels are low at the end of vitellogenesis, steroidogenic structures remain sensitive to an exogenous hypophysial stimulation. Secretion ability differs within individuals correlation coefficient between total estimated c-GTH and E2 = 0,15).

International audience; In fish there are few data on the gonadotropin-releasing hormone (Gn-RH) neurosecretory activity, which could explain long- and short-term variations of the gonadotropin secretion. There is no biological species specificity between mammal and fish Gn-RH; although there is a structural difference, they are, on the contrary, characterized by a high immunological specificity which does not allow measurement of fish Gn-RH using radioimmunoassay for LH-RH. We have synthesized salmon Gn-RH according to the formula recently proposed by Sherwood (N. Sherwood, L. Eiden, M. Brownstein, J. Spies, J. Rivier, and W. Vale, 1983. Proc. Natl. Acad. Sci. USA 80, 2794-2798). Its activity has been tested by its ability to stimulate the gonadotropin hormone (GtH) secretion in vivo in testosterone-implanted juvenile rainbow trout, and for the recognition of synthesized Gn-RH (s-Gn-RH) perykaria by a specific antibody raised against the s-Gn-RH in regions of the brain described as containing LH-RH immunoreactive-like material. A radioimmunoassay has been developed for the salmon Gn-RH, and its specificity to measure trout Gn-RH has been tested. Using this assay, the brain and pituitary Gn-RH contents have been measured throughout the final phases of maturation and ovulation. Brain Gn-RH increases from the end of vitellogenesis (8.9 +/- 0.76 ng/brain) to ovulation (more than 15 ng/brain). Pituitary Gn-RH is lower (1.58 +/- 0.69 ng/pituitary) at the end of vitellogenesis and follows a similar profile as in the brain, except for a significant decrease just prior the beginning of oocyte maturation. The correlations between Gn-RH levels and GtH pituitary and plasma levels show that total brain Gn-RH is never correlated to the GtH, suggesting that the increase in the brain Gn-RH content is related to a Gn-RH system closely related to maturation and ovulation, which remains to be investigated. On the contrary, pituitary Gn-RH levels are well correlated with pituitary and plasma GtH levels, indicating that pituitary Gn-RH levels might represent a good index of the Gn-RH neurosecretory activity in the fish hypothalamohypophysial complex, given the absence of a portal system in teleost.

National audience

International audience; Le méthallibure administré en bains à la dose de 2 p.p.m. entraîne chez le poisson rouge (Carassius auratus) une inhibition de la spermatogenèse qui intéresse toutes les cellules germinales à l'exception des spermatogonies A. Lorsque les mâles soumis à ce traitement reçoivent en même temps des injections de poudre hypophysaire brute de Carpe, la spermatogenèse est maintenue et même fortement stimulée. Après la suppression du traitement au méthallibure, la spermatogenèse se rétablit complètement en 20 jours, mais la restauration est plus importante si les animaux reçoivent des injections de poudre hypophysaire brute de Carpe.

Des extraits hypothalamiques de carpe sont capables d'augmenter significativement la libération d'hormone gonadotrope d'hypophyses de carpes incubées in vitro. Il existerait donc chez les poissons comme chez les mammifères un facteur hypothalamique de libération d'hormone gonadotrope (G-RF).

SUMMARY The level of gonadotrophin measured by radioimmunoassay in fully mature male goldfish was about 15 ng carp gonadotrophic hormone (c-HG)/ml plasma and 30 μg c-HG/g pituitary (wet weight). After treatment for 35 days with methallibure (added to the water at the rate of 2 p.p.m./day), the level of gonadotrophin in the blood was very low and remained at the pretreatment level in the pituitary. This suggested that releasing factor might control either synthesis or discharge of gonadotrophin from the pituitary. These results have also shown that type B spermatogonia and meiosis were gonadotrophin dependent but that the development of spermatocytes into spermatids did not require high concentrations of gonadotrophin. Spermiation was suppressed when the concentration of c-HG dropped below 10 ng/ml plasma.

Des extraits hypothalamiques de Carpe ou de Truite stimulent la sécrétion in vitro de LH par des hypophyses de Bélier. lnversement des extraits hypothalamiques de Bélier stimulent la sécrétion de c-HG par des hypophyses de Carpe. Ce résultat permet d'étendre aux Poissons la non spécificité des hormones hypothalamiques gonadotropes déjà montrée in vivo et in vitro à l'intérieur de la classe des mammifères, et entre les mammifères et les oiseaux

Testosterone : effects on the maintenance of spermatogenesis in intact and hypophysectomized goldfish (Carassius auratus)

International audience; Il existe une confusion importante dans la notion de spécificité d’action des hormones gonadotropes de Poissons. Cette notion a été précisée en utilisant deux méthodes différentes : d’une part la comparaison des activités biologiques de différents extraits hypophysaires de Poissonssur un même récepteur testiculaire, d’autre part la détermination de leur comportement immunologique vis-à-vis d’anticorps hautement spécifiques dirigés contre l’hormone gonadotrope de Carpe c-HG et o-LH. La spermatogenèse du Carassin, Carassius auratus et du Guppy, Poecilia reticutata hypophysectomisés ne peut être regénérée quantitativement qu’avec des hormones gonadotropes ou extraits hypophysaires autologues d’une espèce donneuse très proche de l’espèce receveuse. La technique de compétition isotopique vis-à-vis d’anticorps spécifiques d’une entité moléculaire définie, donne des résultats comparables. Seuls des extraits hypophysaires de Carpe et d’autres Cyprinidés peuvent déplacer de l’hormone de Carpe marquée à l’iode 131 I (c-HGI 131) du complexe c-HGI131, anti c-HG. Les hormones mammaliennes o-LH, o-FSH et HCG n’ont en aucun cas montré d’activité sur la spermatogenèse du Carassin et du Guppy ni d’affinité vis-à-vis d’anticorps dirigés spécifiquement contre une hormone gonadotrope de Poisson. Ces résultats confirment l’existence d’une spécificité zoologique d’action des hormones gonadotropes hypophysaires entre les Mammifères et les poissons teléostéens et à l'intérieur même des différentes familles de téléostéens

BACKGROUND AND OBJECTIVE: As an important achievement in industrialization and urbanization, depression can be much related to the oral hygiene especially periodontal indexes which are a symbol of tooth and oral hygiene and their surrounding tissues. The purpose of this study was to compare the periodontal indexes in individuals with and without depression disorders.METHODS: The present study was carried out in the form of a questionnaire, examination, and recording in the information form. The subjects were divided into two groups of 50 a group included the patients suffering from depression who hospitalized in Neuropsychology ward of Panje Azar hospital in Gorgan, Iran and the control group included either the patients who referred to department of oral medicine and diagnosis of Babol dental school or the people accompanying the patients who had claimed to have no history of depression. The periodontal indexes of the study included: Silness and Loe plaque index, Loe gingival index, pocket depth analysis, as well as bleeding on probing. The information related to each patient was recorded in the form and then two groups were compared.FINDINGS: In the present study, the pocket probing were 2.7692±0.5991 and 2.2917±0.4643 in the control and case groups, respectively (p= 0.009). The Plaque Index means were 1.5385±0.1 and 7763.2593±0.5257 in the control and case groups, respectively. Furthermore, the GI and BOP difference between the two groups were not significant. Moreover, there was no significant relationship between the mean of all the analyzed indexes and the increase of depression.CONCLUSION: The results of the present study indicate a vivid relationship between the depth of pocket probing and depression. Nevertheless, none of the periodontal indexes were obviously related to the degree of depression.Please cite this article as follows:Jenabian N, Taziki SA, Hosseini R, Kiakojouri A, Ehsani H. Comparison of Periodontal Indexes in Individuals with and without Depression Disorders. J Babol Univ Med Sci 2013 15(6):90-94.

The adenohypophysis contains high-affinity binding sites for antidiabetic sulfonylureas that are specific blockers of ATP-sensitive K+ channels. The binding protein has a M(r) of 145,000 +/- 5000. The presence of ATP-sensitive K+ channels (26 pS) has been demonstrated by electrophysiological techniques. Intracellular perfusion of adenohypophysis cells with an ATP-free medium to activate ATP-sensitive K+ channels induces a large hyperpolarization (approximately 30 mV) that is antagonized by antidiabetic sulfonylureas. Diazoxide opens ATP-sensitive K+ channels in adenohypophysis cells as it does in pancreatic beta cells and also induces a hyperpolarization (approximately 30 mV) that is also suppressed by antidiabetic sulfonylureas. As in pancreatic beta cells, glucose and antidiabetic sulfonylureas depolarize the adenohypophysis cells and thereby indirectly increase Ca2+ influx through L-type Ca2+ channels. The K+ channel opener diazoxide has an opposite effect. Opening ATP-sensitive K+ channels inhibits growth hormone secretion and this inhibition is eliminated by antidiabetic sulfonylureas.