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.
Massfelder
T
T
Laboratoire de Physiologie Cellulaire Rénale, Université Louis Pasteur, Strasbourg, France.
Saussine
C
C
Simeoni
U
U
Enanga
B
B
Judes
C
C
Helwig
J J
JJ
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