Abstract
The goal of this study was to determine whether galanin affects the mean plasma concentrations of metabolic parameters such as thyroxine (T4), triiodothyronine (T3), growth hormone (GH), insulin, glucagon, glucose, fatty acid and urea in goats fed diets differing in energy content. Sixteen goats were randomly divided into 4 groups. Animals in groups 1 and 2 were fed 100% and animals in groups 3 and 4 were fed 50% energy content in the diet for 20 days. After 20 days, animals in groups 1 and 3 received a daily infusion of 1 μg galanin and groups 2 and 4 received a daily infusion of 2 μg galanin into their third ventricle for 5 days. Blood samples were collected daily from the jugular vein before infusion on day 4 until 4 days after the last infusion of galanin. Samples were assayed for plasma T3, T4, GH, insulin and glucagon concentrations by double-antibody RIA. Glucose, fatty acid and urea concentrations were also measured. Lower dietary energy intake and infusions of 1 and 2 μg galanin significantly (p<0.01) decreased the mean plasma concentrations of T3, T4, insulin and glucose and significantly (p<0.01) increased the mean plasma concentrations of GH, glucagon, fatty acid and urea of the animals in groups 3 and 4. Different dosages of the galanin infusions did not change the plasma concentrations of the metabolic parameters in the animals fed a normal dietary energy content. The results of this experiment indicated that galanin may negatively affect T3, T4, insulin and glucose and increase GH, glucagon, fatty acid and urea in goats with negative energy balance, but not in those with positive energy balance.
Highlights
Of growth hormone (Kaplan et al, 1986; Hermansen, 1988; Merchentaler et al, 1990; Legakis, 2005; Stavroula et al., Galanin is a 29-amino-acid neuropeptide that is mostly 2006)
Most of the above studies were conducted in found in ventral structures
Changes in basal metabolic rate caused by different dietary energy content are accompanied by changes in secretion of thyroid hormones
Summary
Of growth hormone (Kaplan et al, 1986; Hermansen, 1988; Merchentaler et al, 1990; Legakis, 2005; Stavroula et al., Galanin is a 29-amino-acid neuropeptide that is mostly 2006). Most of the above studies were conducted in found in ventral structures Based on its neuron distribution in levels.Ruminants have a different metabolism from that of ventral structures, galanin coexists with many other neurons. It. For example, in the hypothalamic area, galanin coexists is assumed that the control of feeding behavior is different with neurons secreting different neurotransmitters such as from that of nonruminants. GHRH, GABA, noradrenaline, 5-hydroxytryptamine (5- the orexigenic effect of galanin on metabolic hormones in HT) and NPY (Hökfelt et al, 1987; Holets et al, 1988). Ruminants fed diets of different energy content. One of the parameters in goats fed diets differing in energy content
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
