Growth hormone inhibits renotropic action of luteinizing hormone-isoform(s).
We recently purified luteinizing hormone (LH)-isoforms with renotropic activity from ovine pituitaries based on the stimulation of [3H] thymidine incorporation into renal DNA of castrated-hypophysectomized rats. In this study, we examined the hormonal interactions between ovine growth hormone (GH) and this LH-isoform in renal DNA synthesis. A single injection of LH-isoform (40 micrograms) significantly increased [3H] thymidine incorporation, but an injection of GH (200 micrograms) did not, during experimental periods of up to 26 hours. Repetitive ovine GH treatment (5 days) did not change basal [3H] thymidine incorporation, either, although its biological activity was evidenced by an increase in insulin-like growth factor-I (IGF-I). Stimulated [3H] thymidine incorporation by LH-isoform (100 micrograms) was significantly suppressed by an injection of GH (200 micrograms) and was, to a greater extent, by repetitive treatment with GH (200 micrograms/day, for 3 or 5 consecutive days). These results demonstrated one example of the effect of complex hormonal interactions on kidney growth.
Nomura
K
K
Department of Medicine, Tokyo Women's Medical College, Japan.
Nose
J
J
Shizume
K
K
D000818:Animals; D004247:DNA / Q000378:metabolism; D013006:Growth Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D007279:Injections, Subcutaneous; D007536:Isomerism; D007668:Kidney / Q000187:drug effects* / Q000378:metabolism; D007986:Luteinizing Hormone / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D014316:Tritium
D014316:Tritium; D007986:Luteinizing Hormone; D013006:Growth Hormone; D004247:DNA; D013936:Thymidine