Evidence for adenylyl cyclase-dependent receptors for parathyroid hormone (PTH)-related protein in rabbit kidney glomeruli.
Studies were conducted to test whether parathyroid hormone-related protein (PTHrP) is able to stimulate adenylate cyclase activity in isolated rabbit glomeruli. Maximal stimulations were reached at 10(-7) M of human PTHrP-(1-34) or rat PTH-(1-34) and showed a 3-3.3 fold increase over basal activity. The potency (EC50) values were close to 10(-9) M. The guanyl nucleotide GTP, at 10(-5) M, potentiated the effect of PTH and PTHrP but reduced their potency. The combined effect of maximal concentrations of PTHrP and PTH was not additive, and the PTH antagonist [Nle8.18, Tyr34]-bPTH-(3-34)amide inhibited both PTHrP- and PTH-stimulated adenylate cyclase activities. These findings suggest that PTHrP could affect glomerular function through changes in glomerular cAMP content by interaction with PTH receptors.
Laboratoire de Physiologie Cellulaire Rénale, Université Louis Pasteur, Strasbourg, France.
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T
Massfelder
C
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Saussine
U
U
Simeoni
B
B
Enanga
C
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Judes
J J
JJ
Helwig
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D004789:Enzyme Activation; D007678:Kidney Glomerulus / Q000201:enzymology / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D010281:Parathyroid Hormone / Q000378:metabolism*; D044162:Parathyroid Hormone-Related Protein; D011506:Proteins / Q000378:metabolism*; D011817:Rabbits; D011956:Receptors, Cell Surface / Q000378:metabolism*; D018016:Receptors, Parathyroid Hormone
D010281:Parathyroid Hormone; D044162:Parathyroid Hormone-Related Protein; D011506:Proteins; D011956:Receptors, Cell Surface; D018016:Receptors, Parathyroid Hormone; D007770:L-Lactate Dehydrogenase; D000262:Adenylyl Cyclases