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Full-Text Articles in Medicine and Health Sciences
Kisspeptin Receptor Agonist (Ftm080) Increased Plasma Concentrations Of Luteinizing Hormone In Anestrous Ewes, Brian K. Whitlock, Joseph A. Daniel, Lisa L. Amelse, Valeria M. Tanco, Kelly A. Chameroy, F Neal Shrick
Kisspeptin Receptor Agonist (Ftm080) Increased Plasma Concentrations Of Luteinizing Hormone In Anestrous Ewes, Brian K. Whitlock, Joseph A. Daniel, Lisa L. Amelse, Valeria M. Tanco, Kelly A. Chameroy, F Neal Shrick
Valeria M Tanco
Kisspeptin receptor (KISS1R) agonists with increased half-life and similar efficacy to kisspeptin in vitro may provide beneficial applications in breeding management of many species. However, many of these agonists have not been tested in vivo. These studies were designed to test and compare the effects of a KISS1R agonist (FTM080) and kisspeptin on luteinizing hormone (LH) in vivo. In experiment 1 (pilot study), sheep were treated with FTM080 (500 pmol/kg BW) or sterile water (VEH) intravenosuly. Blood was collected every 15 min before (1 hr) and after (1 hr) treatment. In experiment 2, sheep were treated with KP-10 (human Metastin …
Kisspeptin Receptor Agonist (Ftm080) Increased Plasma Concentrations Of Luteinizing Hormone In Anestrous Ewes, Brian K. Whitlock, Kelly A. Chameroy, Rebecca R. Payton, Shinya Oishi, Nobutaka Fujii, Joseph A. Daniel
Kisspeptin Receptor Agonist (Ftm080) Increased Plasma Concentrations Of Luteinizing Hormone In Anestrous Ewes, Brian K. Whitlock, Kelly A. Chameroy, Rebecca R. Payton, Shinya Oishi, Nobutaka Fujii, Joseph A. Daniel
Brian K Whitlock, PhD, DVM, DACT
Kisspeptin (KP) and the KP receptor (Kiss1r) are integral to central regulation of the gonadotropic-axis. The demonstration that intravenous infusion of KP can stimulate gonadotropin secretion and ovulation in seasonally anestrous female sheep offers a means of manipulating the reproductive axis. However, KP may be of limited clinical use because of the short circulating half-life. Kiss1r agonists with increased half-life and similar efficacy to 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 and compare the effects of …
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.
Selected Hormonal And Neurotransmitter Mechanisms Regulating, James L. Sartin, Joseph A. Daniel, Brian K. Whitlock, Robyn R. Wilborn
Selected Hormonal And Neurotransmitter Mechanisms Regulating, James L. Sartin, Joseph A. Daniel, Brian K. Whitlock, Robyn R. Wilborn
Brian K Whitlock, PhD, DVM, DACT
Appetite control is a major issue in normal growth and in suboptimal growth performance settings. A number of hormones, in particular leptin, activate or inhibit orexigenic or anorexigenic neurotransmitters within the arcuate nucleus of the hypothalamus, where feed intake regulation is integrated. Examples of appetite regulatory neurotransmitters are the stimulatory neurotransmitters neuropeptide Y (NPY), agouti-related protein (AgRP), orexin and melanin-concentrating hormone and the inhibitory neurotransmitter, melanocyte-stimulating hormone (MSH). Examination of messenger RNA (using in situ hybridization and realtime PCR) and proteins (using immunohistochemistry) for these neurotransmitters in ruminants has indicated that physiological regulation occurs in response to fasting for several …
Changes In Plasma Concentrations Of Growth Hormone And Luteinizing Hormone In Ewes Following Central And Peripheral Treatment With Kisspeptin, Brian K. Whitlock, Joseph A. Daniel, Barbara P. Steele, James L. Sartin
Changes In Plasma Concentrations Of Growth Hormone And Luteinizing Hormone In Ewes Following Central And Peripheral Treatment With Kisspeptin, Brian K. Whitlock, Joseph A. Daniel, Barbara P. Steele, James L. Sartin
Brian K Whitlock, PhD, DVM, DACT
Kisspeptin (KP), a neuroendocrine regulator of gonadotropin releasing hormone, has been hypothesized as an integrator of nutrition and hormones critical to metabolism and regulation of reproduction. Recent evidence suggests growth hormone (GH) secretion may be influenced by KP. The objective of this study was to determine if the GH stimulatory effect of KP is due to actions on the hypothalamus or anterior pituitary gland in ewes. Adult ovariectomized ewes (n=8) were fitted with intracerebroventricular (ICV) cannula to facilitate central administration of experimental treatments. Ewes received one of eight treatments [four intravenously (IV) and four ICV]. Peripheral treatments [0 (Veh), 100, …
Changes In Plasma Concentrations Of Leptin In Ewes During Pregnancy, Joseph A. Daniel, A B. Milam, M E. Gafnea, Brian K. Whitlock, D H. Keisler
Changes In Plasma Concentrations Of Leptin In Ewes During Pregnancy, Joseph A. Daniel, A B. Milam, M E. Gafnea, Brian K. Whitlock, D H. Keisler
Brian K Whitlock, PhD, DVM, DACT
Previous research has demonstrated circulating concentrations of leptin increase in ewes during mid pregnancy then decline in late pregnancy and early lactation. The objective of this study was to more narrowly define the timing of changes in circulating concentrations of leptin with pregnancy in ewes. Katahdin ewes (n= 19) located at latitude 34.275 and longitude -85.183 (Mount Berry, GA) were utilized. Blood samples were collected weekly via jugular veinpuncture beginning immediately before ram exposure on September 23 and continuing until 4 weeks post-lambing. Ewes were exposed to a ram fitted with a marking harness for a 63 day breeding season. …
A Critical Evaluation Of Serum Methylmalonic Acid And Vitamin B12 For The Assessment Of Cobalt Deficiency Of Growing Lambs In New Zealand, Tini Gruner, J Sedcole, J Furlong, A Sykes
A Critical Evaluation Of Serum Methylmalonic Acid And Vitamin B12 For The Assessment Of Cobalt Deficiency Of Growing Lambs In New Zealand, Tini Gruner, J Sedcole, J Furlong, A Sykes
Dr Tini M Gruner
AIM: To derive reference ranges for serum methylmalonic acid (MMA) for the diagnosis of cobalt/vitamin B12-responsiveness in lambs and critique existing serum vitamin B12 reference ranges. METHODS: Individual animal data from earlier supplementation trials, involving 225 ewes, 106 suckling lambs, 301 lambs during the suckling and post-weaning periods and 414 weaned lambs, for which weight gain to supplementation was observed, were used to derive relationships between serum vitamin B12 and MMA, and liveweight gain. RESULTS: Serum MMA concentrations were rarely elevated above the norm of <2 >μmol/L when serum vitamin B12 concentrations were >375 pmol/L, and not elevated into the range …
Infected Cell Types In Ovine Lung Following Exposure To Bovine Respiratory Syncytial Virus, J. T. Meehan, R. C. Cutlip, H. D. Lehmkuhl, J. P. Kluge, Mark R. Ackermann
Infected Cell Types In Ovine Lung Following Exposure To Bovine Respiratory Syncytial Virus, J. T. Meehan, R. C. Cutlip, H. D. Lehmkuhl, J. P. Kluge, Mark R. Ackermann
Mark R. Ackermann
Sixteen adult sheep (ten females, six males obtained from a closed flock at National Animal Disease Center, Ames, IA) were experimentally infected with bovine respiratory syncytial virus strain 375 (BRSV), and lung tissues were stained for viral antigen. Two infected sheep were euthanatized at each of the following post-inoculation times: 12, 24, 36, 48, 72, 96, 144, and 192 hours. Lung, nasal turbinates, trachea, right cranial bronchial and mediastinal lymph nodes, liver, and spleen were collected for histologic evaluation. An indirect immunoperoxidase technique was performed on routine paraffin-embedded sections of lung tissue, trachea, turbinates, and bronchial and mediastinal lymph nodes …