TY - JOUR
T1 - Comparison of GH‐stimulation by GH‐RH(1‐29)NH2 and an agmatine29 GH‐RH analog, after intravenous, subcutaneous and intranasal administration and after pulmonary inhalation in rats
AU - PINSKI, JACEK
AU - YANO, TETSL
AU - GROOT, KATE
AU - ZSIGO, JOZSEF
AU - REKASI, ZOLTAN
AU - COMARU‐SCHALLY, ANA MARIA
AU - SCHALLY, ANDREW V.
PY - 1993/3
Y1 - 1993/3
N2 - Many studies have shown that human GH-RH(1-29)NH2 possesses full intrinsic activity of GH-RH(1-44)NH2 in vitro and in vivo. This investigation was performed to evaluate the efficacy of GH-RH(1-29)NH2 given by different routes of administration in stimulating GH release in rats. In each case GH-RH(1-29)NH2 was administered intravenously, subcutaneously, intranasally and by pulmonary inhalation at two different doses to groups of seven male rats. At a dose of 150 μg/kg GH-RH(1-29)NH2, the magnitude of GH response was significantly higher for the pulmonary inhalation group (355 ± 33.2 ng GH/mL) than for the subcutaneous group (246 ± 36 ng GH/mL) or for the intranasal group (175 ± 30 ng GH/mL). The group injected intravenously with GH-RH(1-29)NH2 at a dose of 2.5 μg/kg showed the highest response, GH levels reaching 877.2 ± 115 ng/mL. A similar pattern of responses was obtained for the superactive GH-RH(1-29)agmatine29 analog, MZ-3-149, at doses that were 50 times lower. Our results indicate a high bioavailability of GH-RH(1-29)NH2 or analog MZ-3-149 administered by a convenient pulmonary inhalation route. The GH-releasing effect of GH-RH(1-29)NH2 or analog MZ-3-149 delivered by pulmonary inhalation is superior to subcutaneous and intranasal administration.
AB - Many studies have shown that human GH-RH(1-29)NH2 possesses full intrinsic activity of GH-RH(1-44)NH2 in vitro and in vivo. This investigation was performed to evaluate the efficacy of GH-RH(1-29)NH2 given by different routes of administration in stimulating GH release in rats. In each case GH-RH(1-29)NH2 was administered intravenously, subcutaneously, intranasally and by pulmonary inhalation at two different doses to groups of seven male rats. At a dose of 150 μg/kg GH-RH(1-29)NH2, the magnitude of GH response was significantly higher for the pulmonary inhalation group (355 ± 33.2 ng GH/mL) than for the subcutaneous group (246 ± 36 ng GH/mL) or for the intranasal group (175 ± 30 ng GH/mL). The group injected intravenously with GH-RH(1-29)NH2 at a dose of 2.5 μg/kg showed the highest response, GH levels reaching 877.2 ± 115 ng/mL. A similar pattern of responses was obtained for the superactive GH-RH(1-29)agmatine29 analog, MZ-3-149, at doses that were 50 times lower. Our results indicate a high bioavailability of GH-RH(1-29)NH2 or analog MZ-3-149 administered by a convenient pulmonary inhalation route. The GH-releasing effect of GH-RH(1-29)NH2 or analog MZ-3-149 delivered by pulmonary inhalation is superior to subcutaneous and intranasal administration.
KW - GH‐RH analog
KW - growth hormone
KW - pulmonary inhalation
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U2 - 10.1111/j.1399-3011.1993.tb00332.x
DO - 10.1111/j.1399-3011.1993.tb00332.x
M3 - Article
C2 - 8463048
AN - SCOPUS:0027468939
VL - 41
SP - 246
EP - 249
JO - International journal of protein research
JF - International journal of protein research
SN - 0367-8377
IS - 3
ER -