Independent Protein Kinase Activity Research Articles

Chick heart plasma membranes: Isolation and analysis of autophosphorylation

Plasma membranes have been isolated from hearts of 10-day embryonic and newborn chicks. The membranes obtained were highly enriched in muscarinic acetylcholine receptors, K + -stimulated, ouabain-sensitive p-nitrophenylphosphatase and 5′-nucleotidase. There was little contamination of the membrane fractions by the mitochondrial membranes or by contractile proteins. The autophosphorylation of the isolated membrane fractions was analyzed by measuring 32P incorporation from [γ- 32P]ATP into total membrane protein and into individual membrane components. Membranes obtained from embryonic hearts contained significantly more cAMP-dependent and -independent protein kinase activities than membranes from newborn chick hearts. Treatment of the membranes with Triton X-100 or the peptide ionophore alamethicin increased phosphorylation in membranes from either newborn or embryonic hearts. Membranes from embryonic hearts contained substrates for membrane-bound cAMP-dependent and -independent protein kinases either not observed or present in low amount in membranes from newborn hearts, and vice-versa. Notably, a 38 kDa protein was markedly phosphorylated by endogenous cAMP dependent protein kinase in plasma membrane enriched fractions from embryonic hearts. This phosphoprotein was not easily detected in any fraction obtained from newborn hearts. One cAMP-dependent phosphoprotein had an M r of 27 000 or 11 000, depending on the conditions used to solubilize it. This protein was present in sarcolemma-enriched membranes as well as membrane fractions containing sarcoplasmic reticulum. There was more of this phosphoprotein in newborn heart membranes than in embryonic hearts. The phosphorylation of this protein was markedly enhanced by the peptide ionophore alamethicin. A second cAMP-dependent phosphoprotein with an M r of 27 000 was also detected in the sarcolemma-enriched membranes.

Presence of cyclic nucleotide-Ca2+ independent protein kinase in bovine brain coated vesicles.

Coated vesicles, which are membrane vesicles enclosed by a polyhedral protein lattice, are involved in many cellular events, including intracellular membrane transport and protein secretion, in which they must be able to undergo repeated membrane fusion and fission. The icosahedral lattice of protein surrounding the core of coated vesicles is composed predominantly of clathrin, a 180,000 (180 K) molecular weight protein, and other 30K and 36K polypeptides. In native conditions, the basic subunit of the coat consists of a trimer of clathrin with probably three polypeptides of 30K and/or 36K (refs 9-11). Additional minor proteins of 100K and 55K have been reported in purified coated vesicles. We describe here the presence of cyclic nucleotide- and Ca2+-independent protein kinase activity in coated vesicles. This protein kinase phosphorylates specifically a unique 50K protein which can be co-purified with clathrin and seems to be an integral protein of coated vesicles.

Adenosine 3′,5′-cyclic monophosphate dependent and independent protein kinase activities in 1,2-dimethylhydrazine induced rat colon cancer

The adenosine 3′,5′-cyclic monophosphate (cAMP)-dependent and cAMP-independent kinase activities were measured in the 1,2-dimethylhydrazine (DMH) induced rat colon cancer and in untreated colon. Previous studies had shown that intestinal tumors induced by chronic exposure to DMH contained 2-fold less intracellular cAMP. The present findings indicate that reduction in cAMP-dependent protein kinase activities also occur in colon cancer cells. Similar hydrogen ion dependence (pH 6–7) and approximate association constants ( K a ∼ 0.1 μM) were observed for the enzymes existing in both normal and tumor tissues, while the cAMP-dependent tumor protein kinase was found to phosphorylate phosvitin and casein to a greater degree. These recent findings are consistent with the concept that the concentrations of cAMP and activities of its associated enzyme system are inversely related to the cell proliferation state.

Protein kinases in HeLa cells and in human cervix carcinoma.

Extracts of HeLa cell fractions were analyzed by DEAE- and phospho-cellulose chromatography for their range of cyclic AMP-dependent and -independent protein kinase activities phosphorylating histone and/or phosvitin; extractions were by phosphate buffered saline (soluble protein kinases) and the non-ionic detergent NP-40 (membrane-bound protein kinases). The soluble fraction contained (i) cyclic AMP-dependent histone kinases type I and II as evidenced by their behaviour on DEAE-cellulose and inhibition by specific heat- and acid-stable protein kinase inhibitor (PKI) in a dose-related manner; both types I and II as well as their purified catalytic subunit also phosphorylated protamine and - with very low efficiency - casein but not phosvitin; (ii) a histone kinase (H), insensitive to cyclic AMP and PKI, also accepting protamine as substrate but not either casein or phosvitin; (iii) a phosvitin kinase (P), insensitive to cyclic AMP and PKI, which also phosphorylates casein but not histone or protamine. These four enzyme species were also found in NP-40 extracts of 27000 x g residues which, however, contained further histone and phosvitin kinase activities as yet unspecified. NP-40 extracts of the microsomal fraction possessed, besides unspecified histone and phosvitin kinase activity, only the phosvitin kinase P and appeared to be devoid of histone kinases I, II, and H. The occurrence and ratios of the protein kinases classified suggest an ordered distribution over the diverse subcellular fractions of HeLa cells. The overall pattern of soluble and membrane-bound histone and phosvitin kinases in extracts of cervix carcinoma tissue, the in vivo correlate of HeLa cells, closely resembled that of similar extracts of HeLa cells. HeLa cells hence appear, despite their long in vitro history, to express protein kinase activities similar to those of their in vivo ancestors, recommending them as a subject for the study of (certain) human protein kinase systems.

Identification of a specific endogenous inhibitor of a casein kinase (G type) in bovine adrenal cortex as a glycosaminoglycan mixture

Summary Bovine adrenal cortex contains an endogenous factor which selectively inhibits a particular class of cyclic nucleotide independent protein kinase activity (G type casein kinase). This previously purified inhibitor (D. JOB et al. , FEBS Lett., 98 , 303–308) was found to contain typical glycosaminoglycan components. Electrophoretic analysis and selective degradation procedures showed that the inhibitor preparation contained two major glycosaminoglycan moieties identified as heparin-like and chondroitin sulfate-like structures. The casein kinase G inhibitory properties appeared to require intact glycosaminoglycan chains. These findings may suggest a potential role of glycosaminoglycans in the modulation of intracellular protein phosphorylation processes by a particular type of messenger independent protein kinase.

Cyclic nucleotide independent casein kinase (G type) in bovine adrenal cortex Purification and properties of two molecular forms

Two soluble cyclic nucleotide independent protein kinase (ATP: proteinphosphotransferase, EC 2.7.1.37) activities have been purified from bovine adrenal cortex cytosol. Both purified enzymes exhibit the best affinity for acidic substrates such as casein and can use GTP as well as ATP as phosphoryl donor. They can thus be classified as casein kinase of the G type as previously proposed (Cochet C. et al., (1980) Endocrinology 106, 750–757). Whereas the two moieties could be separated using their different affinities toward a phosphocellulose resin, both purified enzymes appeared indistinguishable on the basis of several molecular and catalytic properties. Both G type casein kinase moieties have an identical sedimentation behavior (5.5 S in the presence of 0.5 M NaCl), yield similar patterns upon electrophoresis under denaturing conditions with three major protein components (42 000, 38 000 and 27 000), and show an ability to undergo self-phosphorylation mostly on the 27 000 component. Both enzymes have the same protein and nucleotide (ATP and GTP) substrate specificity, show similar increses in activity in the presence of polyamines and Mg 2+ (optimum at 50 mM) and similar inhibition by NaCl above 0.2 M. The only difference between the two forms of casein kinase (i.e., affinity for phosphocellulose) could not be explained by a different degree of self-phosphorylation nor by a limited proteolytic process during handling and purification. These results suggest that the two active moieties may represent isoenzymatic forms of the G type casein kinase activity in bovine adrenal cortex cytosol.

Isolation of a translational inhibitor from wheat germ with protein kinase activity that phosphorylates initiation factor eIF-2

A translational inhibitor (WGI) has been partially purified from wheat germ extracts. WGI inhibits protein synthesis in rabbit reticulocyte lysates with inhibition kinetics that are similar to those observed in heme-deficiency or by the addition of purified heme-regulated translational inhibitor (HRI). Initiation factor eIF-2 from rabbit reticulocytes overcomes this inhibition. This finding suggests that WGI inhibits protein chain initiation. WGI induced inhibition is enhanced by ATP (2 mM), and overcome by GTP (2 mM) and cyclic-AMP (10 mM). WGI preparations contain a cyclic-AMP independent protein kinase activity that phosphorylates the 38,000-dalton subunit of rabbit reticulocyte eIF-2. The phosphopeptide analyses of eIF-2 phosphorylated by WGI or HRI show that they phosphorylate the same site(s) of eIF-2. HRI phosphorylates the corresponding 38,000-dalton subunit of wheat germ eIF-2. These results obtained with WGI are similar to that of HRI. HRI has been identified as a cyclic-AMP independent protein kinase that phosphorylates the 38,000-dalton subunit of eIF-2 [for review see Ochoa, S. and de Haro, C. (1979) Ann. Rev. Biochem. 48 , 549]. Hence, these findings with wheat germ-a phylogenetically distant eukaryote, raise further the possibility that phosphorylation-dephosphorylation of eIF-2 may be an important general mechanism in the regulation of eukaryotic protein biosynthesis.

Corticotropin stimulates cyclic nucleotide independent protein kinase activity of intact adrenocortical cells

Intact adrenocortical cells possess cyclic nucleotide-independent protein kinase activity which is capable of phosphorylating endogenous proteins and casein when incubated in the presence of [γ- 32P]ATP. The cyclic nucleotide-independent enzyme was dependent on cell number and temperature and had an apparent K m for ATP of 6.5 × 10 −5 M and a V max of 12.5 pmol/3 min/2 × 10 5 cells at 37°C. Phosphorylation of endogenous proteins by this kinase was increased by treatment of intact cells with corticotropin (2.2 nM) for 24 h. In control cells, two endogenous proteins of apparent molecular weights of 39,000 and 76,000 were phosphorylated. In corticotropin-treated cells, another protein of apparent molecular weight of 87,000 was also phosphorylated. Thus, this protein kinase activity, which appears to be located on the plasma membrane, may be involved in mediating longer term actions of corticotropin on the adrenal cortex.

Protein kinases in the subretinal fluid

Samples of subretinal fluid from patients with retinal detachment of various duration were examined. Protein kinase activity increased with the duration of the detachment. The specific activity of the enzyme increased up to 14 days of retinal detachment, subsequently decreased up to 21 days and thereafter remained constant. Cyclic AMP dependent and cyclic AMP independent protein kinase activities were present. The data suggest that protein kinases may be involved in the degradation of rod outer segments during retinal detachment.

Characterization and properties of a protein kinase associated with murine sarcoma-leukemia virus (MSV-MuLV). Endogenous phosphorylation of a unique p10 polypeptide

MSV-MuLV virions produced by the rat embryo fibroblast 78 A 1 cell line and extensively purified by treatment with trypsin (M. Rucheton, D. Blaas and Ph. Jeanteur, Biochimie, in press) were shown to contain an endogenous cyclic AMP independent protein kinase activity which is located within the viral core. Enzymatic properties were investigated and an apparent molecular weight of 40,000 daltons determined by gel filtration. It shows a marked preference for acidic exogenous substrates and especially α-casein. During endogenous reaction, only the viral protein p10 was phosphorylated.

Properties of epinephrine-induced activation of cardiac adenosine 3′,5′-monophosphate-dependent protein kinase

The effects of epinephrine on cyclic AMP content and protein kinase activity were examined in an in situ rat heart preparation. Bolus injection of epinephrine into the superior vena cava caused an increase in the activity ratio (—cyclic AMP/+cyclic AMP) of 12 000 × g supernatant protein kinase. The increase was significant within 5 s and maximal in 10 s. Epinephrine produced a dose-dependent increase in both protein kinase activity ratio and cyclic AMP content. The increases in both parameters exhibited a high degree of correlation. The increase in protein kinase activity ratio observed with low doses of epinephrine (less than or equal to 1 μg/kg) resulted from an increase in independent protein kinase activity (—cyclic 2 AMP) without a change in total protein observ activity (+cyclic AMP). However, the increase in the activity ratio observed with higher doses of epinephrine (greater than 1 μg/kg) was due mainly to a decrease in total protein kinase activity rather than a further increase in independent protein kinase activity. The loss of supernatant total protein kinase activity could be accounted for by an increase in activity associated with particulate fractions obtained from the homogenates. A similar redistribution of protein kinase could be demonstrated by the addition of cyclic AMP to homogenates prepared from hearts not stimulated with epinephrine. These results demonstrate that epinephrine over a wide dose range produces a parallel increase in the content of cyclic AMP and the activation of soluble protein kinase. The findings also suggest that protein kinase translocation to particulate material may depend on the degree of epinephrine-induced enzyme activation.

CYCLIC NUCLEOTIDES and PROTEIN KINASE ACTIVITY IN THE RAT BRAIN POSTMORTEM

Abstract— The components of the cyclic nucleotide system were studied in rat brain at various times after death to determine the stability of the system postmortem. The concentration of cyclic AMP in 4 brain regions was highest 10 min after death and declined to stable levels within 6 h after death. At this time concentrations approximated those normally seen in vitro. The concentration of cyclic GMP in brain regions fell markedly postmortem and was undetectable 6 or 16 h after death. Nor‐epinephrine‐stimulated cyclic AMP accumulation measured in vitro in slices of the cerebral cortex was the same 10 min and 16 h postmortem. In the cerebellum, however, accumulated levels of cyclic AMP were lower 16 h postmortem, although the degree of stimulation elicited by norepinephrine was the same 10 min and 16 h after death. Cyclic AMP‐dependent and independent protein kinase activities were detected in the rat brain at all times after death. There was no change in the cyclic AMP‐dependent enzyme activity postmortem, but activity in the absence of cyclic AMP was significantly higher immediately after death compared to 6 or 16 h postmortem. These studies indicate that it should be possible to study the cyclic AMP system in human brain tissue obtained at autopsy.

The regulation of fatty acid biosynthesis: Simple procedure for the purification of acetyl CoA carboxylase from lactating rabbit mammary gland, and its phosphorylation by endogenous cyclic AMP-dependent and -independent protein kinase activities

A number of key regulatory enzymes in eukaryotic cells are now known to be controlled by phosphorylation-dephosphorylation mechanisms, and there is increasing evidence that these interconversion reactions underlie the short term regulation of metabolism by external physiological stimuli (reviewed [I] ). The rate at which cytoplasmic acetyl CoA is converted to long chain fatty acids is stimulated by insulin in fat cells [2] and inhibited by glucagon in hepatocytes [3] . Acetyl CoA carboxylase has been implicated as the enzyme at which these hormonal effects are exerted, but the mechanisms are not understood in molecular terms. Acetyl CoA carboxylase is completely dependent on the allosteric activator citrate for activity, and it is inhibited by very low concentrations of palmityl CoA [4] . There is also preliminary evidence which indicates that acetyl CoA carboxylase may be regulated by a phosphorylation-dephosphorylation mechanism. Relatively crude preparations from rat liver [S] or bovine mammary gland [6] undergo a time-dependent inactivation if they are incubated with magnesium ions and [Y-~~P] ATP [7-91 and 32P-radioactivity is incorporated into a protein(s) which is precipitated by antiserum raised to a proteolytic fragment of rat liver acetyl CoA carboxylase [7-91 . Furthermore the inactivation can be reversed by incubation with a protein phosphatase preparation partially purified from hen oviduct [9] . If isolated fat cells are incubated with 32P, a protein with a subunit molecular weight corresponding to acetyl CoA carboxylase becomes labelled, and this protein can be precipitated using a monospecific antibody raised to acetyl CoA carboxylase from rat mammary gland [lo] . This experiment shows that the enzyme is phosphorylated in intact cells. We describe here an extremely simple method for the purification of large amounts of undergraded acetyl CoA carboxylase and demonstrate that this preparation can be phosphorylated by two distinct protein kinase activities that are present as trace endogenous contaminants in the preparation.

Cyclic adenosine monophosphate-dependent and -independent protein kinase activity of renal brush border membranes

Kinase(s) in brush border membranes, isolated from rabbit renal proximal tubules, phosphorylated proteins intrinsic to the membrane and exogenous proteins. cAMP stimulated phosphorylation of histone; phosphorylation of protamine was cAMP independent. cAMP-dependent increases in phosphorylation of endogenous membrane protein were small, but highly reproducible. Most of the 32P incorporated into membranes represented phosphorylation of serine residues, with phosphorylthreonine comprising a minor component. cAMP did not alter the electrophoretic pattern of 32P-labeled membrane polypeptides. The small cAMP-dependent phosphorylation of brush border membrane proteins was not due to membrane phosphodiesterase or adenylate cyclase activities. Considerable cAMP was found “endogenously” bound to the membranes as prepared. However, this did not result in preactivation of the kinase since activity was not inhibited by a heat-stable protein inhibitor of cAMP-dependent protein kinases. With intrinsic membrane protein as phosphate acceptor, the relationship between rate of phosphorylation and ATP concentration appeared to follow Michaelis-Menton kinetics. With histone the relationship was complex. cAMP did not affect the apparent K m for histone. One-half maximal stimulation of the rate of histone phosphorylation was obtained with 7 × 10 −8 m cAMP. The K a values for dibutyryl cAMP, cIMP, and cGMP were one to two orders of magnitude greater. Treatment of brush border membranes with detergent greatly increased the dependency of histone phosphorylation on cAMP. Phosphorylations of intrinsic membrane protein and histone were nonlinear with time, due in part to the lability of the protein kinase, the hydrolysis of ATP, and minimally to the presence of phosphoprotein phosphatase in the border membrane. The membrane phosphoprotein phosphatase was unaffected by cyclic nucleotides. Protein kinase activity was also found in cytosolic and crude particulate fractions of the renal cortex. Activity was enriched in the brush border membrane relative to that in the crude membrane preparation. The kinase activities in the different loci were distinct both in relative activities toward different substrates and in responsiveness to cAMP.

The 3′,5′-adenosine-monophosphate system during the larval-adult moulting cycle in the migratory locust, Locusta migratoria

During the larval-adult moulting cycle of the migratory locust the concentration of 3′,5′-AMP and the activities of adenylate cyclase, phosphodiesterase, protein kinase, and phosphorylase a and b were measured in wing pads and wings, and in the integument of the abdomen. In the wing pads the maximum of adenylate cyclase activity precedes the increase in 3′,5′-AMP concentration as well as the binding capacity and the 3′,5′-AMP-dependent activation of the protein kinase. Around ecdysis adenylate cyclase activity shows a minimum, but increases later. 3′,5′-AMP concentration and the nucleotide dependent protein kinase activity are decreasing in the adult locust. The protein kinase activity in absence of 3′,5′-AMP (independent protein kinase plus basal activity of dependent protein kinase) shows the highest activities in the four day old last instar and in the one day old adult. Phosphodiesterase activity stays rather constant during the instar stage but rises after ecdysis. Phosphorylase a and b increase their activities just around ecdysis. In the integument of the abdomen essentially the same pattern of concentration and activity changes can be detected, with the exception that extreme decreases during adult life do not take place.

Characterization of protein kinases from bovine parotid glands The effect of tolbutamide and its derivative on these partially purified enzymes

1. 1.|Four fractions of protein kinase (EC 2.7.1.37) activity (Peak I H, II H, III C and IV C) have been resolved and partially purified from the 100 000 × g supernatant fraction of bovine parotid glands by DEAE-cellulose and phosphocellulose chromatographies. 2. 2.|The protein kinases of Peak I H and II H were adenosine 3′,5′-monophosphate (cyclic AMP)-dependent and had similar enzymic properties. The enzyme activities of Peak III C and IV C were cyclic-AMP independent, but there were some distinct differences between their properties. The protein kinase in Peak III C was activated by 0.2 M NaCl or KCl and phosphorylated casein preferentially as the substrate, utilizing only ATP as a phosphate donor. On the other hand, the protein kinase in Peak IV C was inhibited by univalent salts and preferred phosvitin to casein, utilizing either ATP or GTP as a phosphate donor. 3. 3.|Tolbutamide increased the K m value for ATP and the dissociation constant for cyclic AMP, resulting in the inhibition of cyclic-AMP dependent protein kinase activity in the presence of cyclic AMP. Tolbutamide and its carboxy derivative, 1-butyl-3- p-carboxyphenylsulfonylurea, exerted almost no inhibitory effect on either the cyclic-AMP dependent protein kinase activities in the absence of cyclic AMP or on the cyclic-AMP independent protein kinase activities.

Mode of action of antirheumatic drugs on the cyclic 3?,5?-AMP regulated glycosaminoglycan secretion in fibroblasts

The effect non-steroidal anti-inflammatory drugs on formation and release of glycosaminoglycans (GAG) and cyclic 3',5'-AMP levels was studied in embryonic mouse fibroblasts. The results were compared and correlated with the action of these drugs on cyclic 3',5'-AMP-dependent as well as independent protein kinase obtained from bovine diaphragm. 1. Phenylbutazone dose-dependently decreased cyclic 3',5'-AMP levels and GAG secretion both in unstimulated and PGE1 stimulated cells. 2. Indometacin decreased cyclic 3',5'-AMP levels and GAG secretion only in cells with elevated cyclic 3',5'-AMP levels after stimulation by PGE1. 3. Sodium salicylate decreased cyclic 3',5'-AMP levels in the presence and absence of PGE1. However, GAG secretion was reduced only in cells with elevated cyclic 3',5'-AMP levels, since the drug activated cyclic 3',5'-AMP-independent protein kinase activity, thus presumably precluding changes in GAG formation at low levels of cyclic 3',5'-AMP. 4. Mefenamic acid decreased cyclic 3',5'-AMP levels in cells stimulated by PGE1, whereas GAG secretion was increased both in the absence and presence of PGE1. This increase in GAG secretion was closely correlated to an enhanced cyclic 3',5'-AMP-dependent and independent protein kinase activity. The results indicate that non-steroidal anti-inflammatory drugs may exert their effects on GAG formation by interfering with cyclic 3',-5'-AMP formation or function.

Effects of dibutyryl cyclic AMP on alpha-methyl-d-glucoside accumulation in rabbit kidney.

ARTICLESEffects of dibutyryl cyclic AMP on alpha-methyl-d-glucoside accumulation in rabbit kidneyR Reynolds, and S SegalR Reynolds, and S SegalPublished Online:01 Apr 1974https://doi.org/10.1152/ajplegacy.1974.226.4.791MoreSectionsPDF (1 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInEmailWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformationCited ByNa+ and K+ fluxes stimulated by Na+-coupled glucose transport: Evidence for a Ba2+-insensitive K+ efflux pathway in rabbit proximal tubulesThe Journal of Membrane Biology, Vol. 105, No. 3Characterization of the d-glucose/Na+ cotransport system in the intestinal brush-border membrane by using the specific substrate, methyl α-d-glucopyranosideBiochimica et Biophysica Acta (BBA) - Biomembranes, Vol. 904, No. 1Glucose-dependent respiration in suspensions of rabbit cortical tubulesThe Journal of Membrane Biology, Vol. 78, No. 3Transport of D-Glucose in the Mammalian KidneyEffects of dibutyryl cyclic amp on the transport of α-methyl-d-glucoside and α-aminoisobutyric acid in separated tubules and brush border membranes from rabbit kidneyBiochimica et Biophysica Acta (BBA) - Biomembranes, Vol. 558, No. 1The Role of Glutathione in Transport Activity in KidneyCyclic nucleotide phosphodiesterases of the renal cortexThe Journal of Membrane Biology, Vol. 37, No. 1Transport and metabolism of adenosine 3':5'-monophosphate and N6, O2'-dibutyryl adenosine 3':5'-monophosphate by isolated renal tubules.Journal of Biological Chemistry, Vol. 252, No. 19Cyclic adenosine monophosphate-dependent and -independent protein kinase activity of renal brush border membranesArchives of Biochemistry and Biophysics, Vol. 180, No. 2Cyclic nucleotide phosphodiesterases of rabbit renal cortexArchives of Biochemistry and Biophysics, Vol. 174, No. 1Inhibition of protein kinase activity and amino acid and α-methyl-d-glucoside transport by diamideBiochimica et Biophysica Acta (BBA) - Biomembranes, Vol. 419, No. 1Stimulation of p-aminohippuric acid transport in rabbit kidney cortex by parathyroid hormone and adenosine 3′,5′-cyclic monophosphateBiochemical Pharmacology, Vol. 25, No. 2 More from this issue > Volume 226Issue 4April 1974Pages 791-795 Copyright & PermissionsCopyright © 1974 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1974.226.4.791PubMed4362803History Published online 1 April 1974 Published in print 1 April 1974 Metrics

Effects of parathyroid hormone on renal tubular reabsorption of calcium, sodium, and phosphate.

Effects of parathyroid hormone on renal tubular reabsorption of calcium, sodium, and phosphate.