Summary and Implications
A dose-dependent response of GH plasma concentration to icv injection of 3, 10 and 30 µg/kg BW of the GHsecretagogue, L-692,585 (585) was established in Yorkshire barrows (40-45 kg BW). Icv administration of CRH at 150 µg/kg BW did not raise basal GH concentration compared with saline treatment, and icv injection of 585 at three dosages did not significantly alter cortisol plasma concentration. Icv injection of SRIF dose-dependently decreased GH plasma concentration, whereas icv treatment of SRIF + 585 dosedependently increased GH concentration but at peak levels less than seen with 585 alone. Icv injection of pGAL modestly increased GH peak concentration, whereas when given in combination with 585 acutely raised GH plasma concentration. GH plasma concentration remained at basal levels after icv injection of pNPY, whereas when given in combination with 585 modestly elevated GH concentration at peak levels less than seen with 585 alone. The administration of 585 icv elicited a slower and less robust GH response than that following iv 585; desensitization of the GH response occurred following repeated icv 585 but not repeated iv 585. These findings demonstrate that 585, administered iv or icv, is a potent GH-secretagogue and confirm its central role in the pig.
Iowa State University
Cho, Sang-Joon; Lee, Jin-Sook; Mathias, Eric D.; Lkhagvadorj, Sender; Anderson, Lloyd L.; Chang, Ching; and Hickey, Gerard J.
"Central and Peripheral Administration of Growth Hormone
Secretagogue L-692-585, Somatostatin, Neuropeptide Y and
Galanin in Pig: Dose-dependent Effects on Growth Hormone
Animal Industry Report:
AS 657, ASL R2657.
Available at: http://lib.dr.iastate.edu/ans_air/vol657/iss1/81