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Heifer Estrous Cycle Stage Impacts Luteinizing And Growth Hormone Response To Kisspeptin, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Barbara P. Steele, James L. Sartin
Heifer Estrous Cycle Stage Impacts Luteinizing And Growth Hormone Response To Kisspeptin, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Barbara P. Steele, James L. Sartin
Brian K Whitlock, PhD, DVM, DACT
The reproductive neuropeptide, kisspeptin (KP), may have a role in regulation of growth hormone (GH) secretion. Expression of KP and its receptor (Kiss1r) are developmentally and hormonally regulated. This study was conducted to determine the effects of KP on plasma concentrations of luteinizing hormone (LH) and GH in pubertal heifers during different functional reproductive stages. Heifers received a single injection of KP (100 pmole / kg) or saline intravenously during proestrus, estrus, and diestrus, and serial blood samples were collected for 3 hours to determine the response of both LH and GH after treatment. Mean concentrations of LH were increased …
Effect Of Kisspeptin On Regulation Of Growth Hormone, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Herris S. Maxwell, Barbara P. Steele, James L. Sartin
Effect Of Kisspeptin On Regulation Of Growth Hormone, Brian K. Whitlock, Joseph A. Daniel, Robyn R. Wilborn, Herris S. Maxwell, Barbara P. Steele, James L. Sartin
Brian K Whitlock, PhD, DVM, DACT
Kisspeptin ( KP ), a neuroendocrine regulator of reproduction, is hypothesized to be an integrator of metabolism and hormones critical to the regulation of reproduction. Lactation is associated with enhanced growth hormone (GH) responsiveness and reduced fertility. Our study was designed to determine the effects of lactation on KP-stimulated GH and luteinizing hormone (LH) secretion. Five non-lactating and five lactating dairy cows were used in the study. Experiments were conducted with lactating cows at weeks 1, 5 and 11 after parturition. The experimental treatments ( saline and KP [100 and 400 pmol / kg body weight]) were given intravenously and …
The Effect Of Kisspeptin Receptor Agonist (Ftm080) On Luteinizing Hormone In Sheep, Brian K. Whitlock, Joseph A. Daniel, Maria Hes, Barbara P. Steele, James L. Sartin, S. Oishi, N. Fujii
The Effect Of Kisspeptin Receptor Agonist (Ftm080) On Luteinizing Hormone In Sheep, Brian K. Whitlock, Joseph A. Daniel, Maria Hes, Barbara P. Steele, James L. Sartin, S. Oishi, N. Fujii
Brian K Whitlock, PhD, DVM, DACT
Kisspeptin receptor (Kiss1r) agonists with increased half-life and similar efficacy to kisspeptin (KP) in vitro potentially may provide beneficial applications in breeding management of many species. However, many of these agonists have not been tested in vivo. This study was designed to test the effect of a Kiss1r agonist (FTM080) on luteinizing hormone (LH) in vivo. Sheep were treated with FTM080 (500 pmol/kg BW) or sterile water in a 2-ml bolus via the jugular cannula. Serial blood samples were collected every 15-min before (1 hr) and after (1 hr) treatment. Intravenous (IV) injection of FTM080 increased (P < 0.05) LH plasma concentrations through the 45-min sample following treatment. Moreover, the area under the curve of LH in the period from 0 to 60-min following FTM080 treatment was also increased (P < 0.05). These data provide evidence to suggest that FTM080 stimulates the gonadotropic axis of ruminants in vivo.
Method For Somatic Cell Nuclear Transfer In Zebrafish, Kannika Siripattarapravat, Jose Cibelli
Method For Somatic Cell Nuclear Transfer In Zebrafish, Kannika Siripattarapravat, Jose Cibelli
Jose Cibelli
Somatic cell nuclear transfer (SCNT) has been a well-known technique for decades and widely applied to generate identical animals, including ones with genetic alterations. The system has been demonstrated successfully in zebrafish. The elaborated requirements of SCNT, however, limit reproducibility of the established model to a few groups in zebrafish research community. In this chapter, we meticulously outline each step of the published protocol as well as preparations of equipments and reagents used in zebrafish SCNT.