The effect of new growth hormone-releasing peptide (KP 102) on the release of growth hormone in goats
1997
Hashizume, T. (Iwate Univ., Morioka (Japan). Faculty of Agriculture) | Sasaki, K. | Sakai, M. | Tauchi, S. | Masuda, H.
The effects of KP 102 (also named GHRP-2), a new growth hormone-releasing peptide, on the release of growth hormone (GH) were examined in female goat. The intravenous (iv) single injection of both 5 micro-gram (1.12 mu-M) and 10 micro-gram (2.24 mu-M)/kg BW of KP 102 failed to stimulate significant GH release; however, the dose of 20 micro-gram (4.48 mu-M)/kg BW of KP 102 significantly (P0.05) stimulated GH release. GH responses to a series of 5 iv injections of KP 102 (20 micro-gram/kg BW) at 2-h intervals increased plasma GH levels after each injection; however, the responses induced by KP 102 were different from that by GH-releasing factor GRF, 0.5 micro-gram (29.78 nM/kg BW). the GH responses after the injections of KP 102 were a little delayed, and the elevated GH levels gradually decreased to the basal concentrations compared with GRF. Furthermore, small irregular GH peaks that were not observed in GRF appeared throughout the experiments. The GH responses to KP 102 were decreased by repeated injections of KP 102 as observed n GRF. The responses to plasma GH to a single iv injection of GRF (0.25 micro-gram (14.89 nM) or 0.s5 micro-gram/kg BW), KP 102 (20 micro-gram/kg BW) or GRF (0.25 or 0.5 micro-gram/kg BW) plus KP (20micro-gram/kg BW) were examined; however, significant synergistic effects of GH release by both peptides were not observed. The present study shows that KP 102 stimulates GH release in goats
Показать больше [+] Меньше [-]