Pharmacokinetics of a recombinant bovine growth hormone and pituitary bovine growth hormone in lactating dairy cows.
The disposition of pituitary-derived bovine growth hormone (pbST) and of a recombinant bovine growth hormone (rbST) produced by Lilly (somidobove, USAN) were compared after an intravenous bolus administration (36.69 micrograms/kg for pbST and 35 micrograms/kg for rbST) to eight lactating cows in a crossover study. It was shown that dose-dependent parameters (volume of distribution, clearance) were significantly different between the two test articles. The steady mean state volume of distribution (.10 +/- .018 vs .12 +/- .015 L/kg) and clearance (.119 +/- .012 vs .143 +/- .011 L.kg-1.h-1) were lower for the pbST than for the somidobove. In contrast, the mean (+/- SD) residence times were not different for the two test articles (50.0 +/- 8.6 vs 46.9 +/- 5.9 min for pbST and somidobove, respectively). The origin of the difference is unclear, but it cannot be explained by the slight difference between the administered dose of the two test articles (< 5%) because the actual dose rate was used to calculate all dose-dependent parameters.
INRA, Unité Associée de Physiopathologie et de Toxicologie Experimentales, Ecole Nationale Vétérinaire de Toulouse, France.
P L
PL
Toutain
D
D
Schams
M P
MP
Laurentie
T D
TD
Thomson
D000818:Animals; D002417:Cattle / Q000378:metabolism*; D005260:Female; D013006:Growth Hormone / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006207:Half-Life; D007275:Injections, Intravenous / Q000662:veterinary; D007774:Lactation / Q000378:metabolism*; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000493:pharmacokinetics
D011994:Recombinant Proteins; C073294:growth hormone, bovine; D013006:Growth Hormone