Effect of parathyroid hormone on rat renal calcium/calmodulin-dependent protein kinase II.
Rat parathyroid hormone (PTH) stimulates cAMP-dependent protein kinase and protein kinase C activity in the kidney. However, PTH increases intracellular Calcium in primary cultures of proximal tubular cells. We have investigated the possibility that PTH also stimulates Calcium/calmodulin-dependent protein kinase II (CaM kinase II). We have employed the tandem chromatographic column method, using synthetic peptide as a substrate, to measure the renal CaM kinase II activity. PTH (250 nM) stimulated CaM kinase II activity by about 50% after 15 sec., and activity returned to baseline by 2 min. Calmodulin antagonists significantly impaired the stimulatory action of PTH whereas basal levels of CaM kinase II activity were relatively unaffected. This study demonstrates that PTH does activate CaM kinase II in renal tissue, and suggests another pathway for the actions of PTH in the kidney.
Geriatric Research, Education, and Clinical Center VA Medical Center, St. Louis, MO 63125.
R
R
Nemani
N
N
Wongsurawat
H J
HJ
Armbrecht
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002852:Chromatography, Ion Exchange; D004305:Dose-Response Relationship, Drug; D036341:Intercellular Signaling Peptides and Proteins; D007672:Kidney Cortex / Q000187:drug effects* / Q000201:enzymology; D008297:Male; D010281:Parathyroid Hormone / Q000494:pharmacology*; D010455:Peptides; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D013379:Substrate Specificity
D017871:Calcium-Calmodulin-Dependent Protein Kinases; D036341:Intercellular Signaling Peptides and Proteins; D010281:Parathyroid Hormone; D010455:Peptides; D011494:Protein Kinases; C063391:syntide-2