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Pituitary Extract (pituitary + extract)
Selected AbstractsGrowth, Maturation, Induced Spawning, and Production of the First Generation of South American Catfish, Pseudoplatystoma sp., in North AmericaJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2008Konrad Dabrowski Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11-ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11-h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 109 and 15.5 × 109 spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii. [source] Induced ovulation of yellow catfish (Pelteobagrus fulvidraco) using a combination of a gonadotrop-releasing hormone analogue and domperidoneAQUACULTURE RESEARCH, Issue 8 2010Youji Wang Abstract The effects of an intraperitoneal hormone injection of gonadotropin-releasing hormone agonist (D-Ala6, Pro9 -NEt GnRHa) alone or in combination with a dopamine antagonist, domperidone (DOM), on ovulation induction in yellow catfish Pelteobagrus fulvidraco were tested. The hormone treatments were as follows: 6 mg kg,1 body weight (BW) of carp pituitary extract as a positive control, GnRHa 10, 20, 40 and 80 ,g kg,1 BW and a combination of GnRHa and DOM as follows: 10 ,g+5 mg, 20 ,g+10 mg, 40 ,g+20 mg and 80 ,g+40 mg kg,1 BW. Physiological saline (0.7% NaCl) was used as a negative control. Significant differences in the ovulation ratio, latency period and ovulation index (OI) were observed among treatments (P<0.05). The combination of GnRHa and DOM at doses of 40 ,g+20 mg kg,1 BW had higher values of the ovulation ratio and OI, and a shorter latency period compared with other treatments. The highest OI in GnRHa treatments was only 56.67%, suggesting a dopaminergic tone on gonadotropin secretion in this fish at the pre-ovulatory stage. Therefore, ovulation can be successfully induced in yellow catfish with 40 ,g kg,1 GnRHa+20 mg kg,1 DOM without affecting the egg quality. [source] Hormone injections enhance the tolerance of land-locked ayu spermatozoa to cryopreservationAQUACULTURE RESEARCH, Issue 16 2009Ken-ichi Yokoi Abstract We evaluated the effects of maturation-stimulating hormones on the post-thaw motility of land-locked form ayu (Plecoglossus altivelis) spermatozoa. Male ayu were administered three intraperitoneal injections of either salmon pituitary extract (SPE; 0.2 or 0.6 mg g,1 BW day,1) or of 17, 20,-dihydroxy-4-pregnen-3-one (DHP; 2 or 10 ,g g,1 BW day,1), the maturation-inducing steroid (MIS) in ayu. Before cryopreservation, the motility of spermatozoa of the SPE- and DHP-treated groups was significantly higher than that of the control group. Similarly, the comparative post-thaw motility (presented as a percentage of the motility obtained before cryopreservation) was significantly higher in the SPE group than in the control; however, there was no significant difference between the DHP group and the control. The effect of SPE and DHP on pre- and post-cryopreservation motility was not dose dependent. Our results suggest that the hormone(s) present in salmon pituitary are effective in enhancing the tolerance of ayu sperm cells to cryopreservation and that the MIS (DHP) is not involved in this process. [source] Early development of the silver catfish Rhamdia quelen (Quoy & Gaimard, 1824) (Pisces:Heptapteridae) from the São Francisco River Basin, BrazilAQUACULTURE RESEARCH, Issue 2 2009Marcelo Pimenta De Amorim Abstract The silver catfish, Rhamdia quelen, is endemic to North, Central and South America with high aquaculture potential and wide acceptance in the market. Breeder fish were subjected to induced reproduction through hypophysation using a crude common carp pituitary extract. Egg characteristics, oocyte surface ultrastructure and histology of larval ontogenesis until whole yolk resorption were described for the first time for this species. Oocytes and semen were obtained by manual extrusion, and fertilization was conducted using the dry method. After fertilization, eggs were kept in incubators at 24 °C. The embryonic development was monitored using a stereomicroscope every 10 min until hatching. To analyse the larval development, larvae samples were collected from incubators daily until the fifth day, fixed in Bouin's fluid and subjected to routine histological techniques. The oocyte extrusion occurred 8 h after the second hormone dose at 26 °C. The oocytes were spherical, non-adhesive and yellow, with a diameter of 1471.75±47.63 ,m. Scanning electron microscopy revealed a thin jelly coat covering the zona radiata in the animal pole around the micropyle. The blastopore closure occurred within 8 h after fertilization, and the fertilization rate was 79.9±5.2% at 24 °C. Embryonic development was completed within 25 h 30 min after fertilization. The complete resorption of the yolk and the formation of the digestive system organs and the mouth opening occurred on the fifth day, indicating a need for exogenous feeding. The results of this study provide information important for improvement in R. quelen culture and management. [source] Immortalization of human urothelial cells by human papillomavirus type 16 E6 and E7 genes in a defined serum-free systemCELL PROLIFERATION, Issue 2 2007N. Carmean In previous studies, urothelial cell cultures were immortalized using retroviral transformation with human papillomavirus type 16 E6 and E7 genes, in undefined culture systems containing serum or bovine pituitary extract. Objective: Due to the variability of results in such systems, we instead developed a procedure for the immortalization of urothelial cells using a defined, serum-free culture system. Method and results: Immortalization through retroviral transformation with human papillomavirus type 16 E6 and E7 was successful, and transformation of urothelial cells conferred an extended over normal lifespan and restored telomerase activity. Transformed cells retained typical morphology and exhibited a similar growth rate, cytokeratin immunoreactivity pattern, and response to growth factors as observed in untransformed cells. Karyotype analysis revealed a gradual accumulation of genetic mutations that are consistent with previously reported mutations in epithelial cells transformed with human papillomavirus type 16 E6 and E7. Conclusion: The ability to extend the in vitro lifespan of cells holds the potential to reduce the continuous need for tissue samples and to enable complete investigations with one cell line. [source] Quantitative peptidomics of mouse pituitary: comparison of different stable isotopic tagsJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 2 2005Fa-Yun Che Abstract Determining the relative levels of neuropeptides in two samples is important for many biological studies. An efficient, sensitive and accurate technique for relative quantitative analysis involves tagging the peptides in the two samples with isotopically distinct labels, pooling the samples and analyzing them using liquid chromatography/mass spectrometry (LC/MS). In this study, we compared two different sets of isotopic tags for analysis of endogenous mouse pituitary peptides: succinic anhydride with either four hydrogens or deuteriums and [3-(2,5-dioxopyrrolidin-1-yloxycarbonyl)propyl]trimethylammonium chloride with either nine hydrogens or deuteriums. These two labels react with amines and impart either a negative charge (succinyl) or a positive charge (4-trimethylammoniumbutyryl (TMAB)). Every endogenous mouse pituitary peptide labeled with the light TMAB reagent eluted from the C18 reversed-phase column at essentially the same time as the corresponding peptide labeled with the heavy reagent. Most of the peptides labeled with succinyl groups also showed co-elution of the heavy- and light-labeled forms on LC/MS. The mass difference between the heavy and light TMAB reagents (9 Da per label) was larger than that of the heavy and light succinyl labels (4 Da per label), and for some peptides the larger mass difference provided more accurate determination of the relative abundance of each form. Altogether, using both labels, 82 peptides were detected in Cpefat/fat mouse pituitary extracts. Of these, only 16 were detected with both labels, 41 were detected only with the TMAB label and 25 were detected only with the succinyl label. A number of these peptides were de novo sequenced using low-energy collisional tandem mass spectrometry. Whereas the succinyl group was stable to the collision-induced dissociation of the peptide, the TMAB-labeled peptides lost 59 Da per H9 TMAB group. Several peptides identified in this analysis represent previously undescribed post-translational processing products of known pituitary prohormones. In conclusion, both succinyl and TMAB isotopic labels are useful for quantitative peptidomics, and together these two labels provide more complete coverage of the endogenous peptides. Copyright © 2005 John Wiley & Sons, Ltd. [source] Regulation and Expression of Progesterone Receptor mRNA Isoforms A and B in the Male and Female Rat Hypothalamus and Pituitary Following Oestrogen TreatmentJOURNAL OF NEUROENDOCRINOLOGY, Issue 3 2002R. E. M. Scott Abstract Progesterone receptors play a central role in neuroendocrine and behavioural regulation. To gain insight into the sex- and tissue-specific regulation of progesterone receptors, protein binding on a progesterone receptor-oestrogen response element and mRNA levels for progesterone receptor (PR)-A and PR-B were compared between female and male rats following oestradiol benzoate replacement treatment in hypothalamic and pituitary tissue. Both male and female pituitary protein extracts demonstrated an increase in nuclear protein binding activity to a progesterone receptor-oestrogen response element following oestradiol benzoate treatment. However, there was a greater difference in total binding activity seen in the female pituitary extracts compared to male pituitary protein extracts. In both cases, reflecting the binding data, oestradiol benzoate pretreatment led to an increase in pituitary PR-B messenger RNA, although this increase was significantly larger in females than in males. Oestradiol benzoate treatment also led to a significant increase in specific binding of hypothalamic nuclear proteins to the progesterone receptor oestrogen response element from both females and male hypothalamic extracts. In addition, PR-B messenger RNA was induced by oestradiol benzoate treatment in the female rat hypothalamus, under circumstances where no PR-A could be detected. The male also demonstrated an increase in PR-B messenger RNA following oestradiol benzoate treatment, with undetectable levels of PR-A, although to a lesser degree than that seen in the female. The predominance of PR-B over PR-A messenger RNA in rat hypothalamus and pituitary, and the quantitative differences between female and male rats, could both contribute to the greater responsiveness of female rats to progesterone with respect to control over luteinizing hormone release from the pituitary, and lordosis behaviour regulated by hypothalamic neurones. [source] Increase in milt production by hormonal treatment in the pejerrey fish Odontesthes bonariensis (Valenciennes 1835)AQUACULTURE RESEARCH, Issue 15 2005Leandro A Miranda Abstract In spite of interest in the cultivation of the pejerrey fish Odontesthes bonariensis (Cuvier & Valenciennes 1835), there are few studies on subjects required to advance this activity. One of the problems is the synchronization of female and male maturation to provide eggs and sperm for larval production. The low volume of expressible milt, either in wild or culture fish, is a major problem. The aim of this work was to study the effectiveness of the administration of different hormones on sperm production in pejerrey. Milt production was enhanced by the injection of human chorionic gonadotropin (hCG) (16.7-fold increase, 625 IU kg,1), carp pituitary extracts (13.5-fold increase, 30 mg kg,1), salmon pituitary extracts (12.8-fold increase, 30 mg kg,1), salmon-type gonadotropin-releasing hormone analogue (GnRH) (16.7-fold increase, 10 ,g kg,1) and mammalian-type GnRH analogue (10.8-fold increase, 20 ,g kg,1). Sperm concentration, motility and the fertilization rate were not statistically different compared with control groups. It was also demonstrated that sperm could be obtained off-season. Taken together, hCG is recommended to stimulate pejerrey spermiation because it is effective in low doses is inexpensive and is widely available. [source] | ||||||||||