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PubMed1984

Kinetic properties of the ATP-dependent Ca2+ pump and the Na+/Ca2+ exchange system in basolateral membranes from rat kidney cortex.

Basolateral plasma membranes from rat kidney cortex have been purified 40-fold by a combination of differential centrifugation, centrifugation in a discontinuous sucrose gradient followed by centrifugation in 8% percoll. The ratio of leaky membrane vesicles (L) versus right-side-out (RO) and inside-out (IO) resealed vesicles appeared to be L:RO:IO = 4:3:1. High-affinity Ca2+-ATPase, ATP-dependent Ca2+ transport and Na+/Ca2+ exchange have been studied with special emphasis on the relative transport capacities of the two Ca2+ transport systems. The kinetic parameters of Ca2+-ATPase activity in digitonin-treated membranes are: Km = 0.11 microM Ca2+ and Vmax = 81 +/- 4 nmol Pi/min X mg protein at 37 degrees C. ATP-dependent Ca2+ transport amounts to 4.3 +/- 0.2 and 7.4 +/- 0.3 nmol Ca2+/min X mg protein at 25 and 37 degrees C, respectively, with an affinity for Ca2+ of 0.13 and 0.07 microM at 25 and 37 degrees C. After correction for the percentage of IO-resealed vesicles involved in ATP-dependent Ca2+ transport, a stoichiometry of 0.7 mol Ca2+ transported per mol ATP is found for the Ca2+-ATPase. In the presence of 75 mM Na+ in the incubation medium ATP-dependent Ca2+ uptake is inhibited 22%. When Na+ is present at 5 mM an extra Ca2+ accumulation is observed which amounts to 15% of the ATP-dependent Ca2+ transport rate. This extra Ca2+ accumulation induced by low Na+ is fully inhibited by preincubation of the vesicles with 1 mM ouabain, which indicates that (Na+-K+)-ATPase generates a Na+ gradient favorable for Ca2+ accumulation via the Na+/Ca2+ exchanger. In the absence of ATP, a Na+ gradient-dependent Ca2+ uptake is measured which rate amounts to 5% of the ATP-dependent Ca2+ transport capacity. The Na+ gradient-dependent Ca2+ uptake is abolished by the ionophore monensin but not influenced by the presence of valinomycin. The affinity of the Na+/Ca2+ exchange system for Ca2+ is between 0.1 and 0.2 microM Ca2+, in the presence as well as in the absence of ATP. This affinity is surprisingly close to the affinity measured for the ATP-dependent Ca2+ pump. Based on these observations it is concluded that in isolated basolateral membranes from rat kidney cortex the Ca2+-ATPase system exceeds the capacity of the Na+/Ca2+ exchanger four- to fivefold and it is therefore unlikely that the latter system plays a primary role in the Ca2+ homeostasis of rat kidney cortex cells.

Adenosine Triphosphate↗
PubMed1991

Cloning and expression of cDNA for a Na/Pi cotransport system of kidney cortex.

A cDNA library from rabbit kidney cortex was screened for expression of Na-dependent transport of phosphate (Pi) using Xenopus laevis oocytes as an expression system. A single clone was eventually isolated (designated NaPi-1) that stimulated expression of Na/Pi cotransport approximately 700-fold compared to total mRNA. The predicted sequence of the Na/Pi cotransporter consists of 465 amino acids (relative molecular mass, 51,797); hydropathy profile predictions suggest six (possibly eight) membrane-spanning segments. In vitro translation of NaPi-1/complementary RNA in the presence of pancreatic microsomes indicated NaPi-1 to be a glycosylated protein; four potential N-glycosylation sites are present in the amino acid sequence. Northern blot analysis demonstrated the presence of NaPi-1/mRNA in kidney cortex and liver; no hybridization signal was obtained with mRNA from other tissues (including small intestine). Kinetic analysis of Na/Pi cotransport expressed by NaPi-1/complementary RNA demonstrated characteristics (sodium interaction) similar to those observed in cortical apical membranes. The alignment of 5 amino acid residues (Gly342/Ala381-Xaa-Xaa-Xaa-Xaa-Leu386-Xaa-Xaa-Xaa-P ro390- Arg391) is consistent with a motif proposed for Na-dependent transport systems. We conclude that we have cloned a cDNA for a Na/Pi cotransport system present in rabbit kidney cortex.

Amino Acid Sequence↗
PubMed1975

Effect of diuretics on ion transport of kidney cortex mitochondria. III. Species difference in calcium accumulation and in ethacrynic acid effect.

Effect of inorganic phosphate (4 X 10(-3) M) on Ca++-accumulation was examined in kidney cortex mitochondria. Ca++-accumulation of rat kidney cortex mitochondria was slightly influenced by inorganic phosphate. On the other hand, dog kidney cortex mitochondria did not accumulate calcium from the incubation medium until the inorganic phosphate had been added. Ca++-accumulation of rabbit kidney cortex mitochondria was markedly stimulated by inorganic phosphate. When ethacrynic acid was added to the reaction medium in the absence of inorganic phosphate, Ca++-accumulation of rat kidney cortex mitochondria was depressed and the decrease in calcium content of rabbit and dog kidney cortex mitochondria was enhanced. In the presence of inorganic phosphate, the inhibition of Ca++-accumulation by ethacrynic acid was observed only on dog kidney cortex mitochondria. Subsequently, the effect of inorganic phosphate (4 X 10(-4) M) and ethacrynic acid (1 X 10(-4) M on Ca++-ATPase was examined in kidney cortex mitochondria. The low concentration of inorganic phosphate (4 X 10(-4) M) activated Ca++-ATPase of kidney cortex mitochondria in all animal species. The greatest activation of Ca++-ATPase occurred in rabbits, but the activity of the enzyme was lower than that in rats and dogs. Inhibition of Ca++-ATPase by ethacrynic acid was depressed by the addition of inorganic phosphate in kidney cortex mitochondria of experimental animals. Ca++-accumulation may be regulated through the stimulating effect of inorganic phosphate and the inhibitory effect of ethacrynic acid on Ca++-ATPase in kidney cortex mitochondria. Species difference in ethacrynic acid effect on Ca++-accumulation in kidney cortex mitochondria of rats, rabbits and dogs is discussed.

Adenosine Triphosphatases↗
PubMed1984

Tamm-Horsfall glycoprotein release from rat kidney cortex slices in vitro.

Rat kidney cortex slices were incubated for 30 min at 37 degrees C in unmodified Krebs-Henseleit buffer containing aldosterone, vasopressin, theophylline, ethacrynic acid, frusemide, spironolactone or ouabain. Tamm-Horsfall glycoprotein (THG) released into the media was measured by radioimmunoassay and at the end of each experiment the slices were homogenized and assayed for THG content. Incubation of kidney cortex slices in unmodified buffer resulted in a significant increase in the slice THG content when compared with pre-incubation levels. The increase was prevented by puromycin or cycloheximide. Incubation in ethacrynic acid (1 mmol/l) or frusemide (10 mmol/l) resulted in a significant increase in release of THG when compared with unmodified buffer. Puromycin or cycloheximide failed to prevent the increased release. THG release induced by ethacrynic acid or frusemide is probably the result of an aggregation-disaggregation reaction on the cell membrane. It is suggested that the action of the chloride inhibiting diuretics, ethacrynic acid and frusemide, is mediated in some way via THG.

Animals↗
PubMed1986

Critical concentration of cadmium in kidney cortex of humans exposed to environmental cadmium.

Cadmium (Cd) was determined in kidney cortex and liver of 173 autopsied Japanese. Subjects consisted of 51 persons from Cd-polluted areas ages between 61-94 years and 122 controls ages between 3-90 years. The mean Cd concentrations for the Cd-polluted group were 35.2 micrograms/g wet wt for kidney cortex and 66.7 micrograms/g wet wt for liver. Corresponding values for the control group aged over 60 were 90.1 and 10.7, respectively. Both liver and kidney cortex Cd were analyzed for 127 subjects (41 Cd-polluted and 86 control subjects). The kidney cortex concentration tended to increase linearly with increasing liver concentrations up to approximately 20 micrograms/g of liver Cd; above this value there was no further increase in kidney cortex level. Only three persons showed kidney cortex Cd levels above 200 micrograms/g. The lowest liver Cd levels of the Cd-polluted subjects with renal damage were around 30 micrograms/g. The critical level of kidney cortex Cd may exist below 200 micrograms/g in humans exposed to environmental Cd. The corresponding value for the liver may be below 30 micrograms/g wet wt.

Adolescent↗
PubMed1996

The effect of the lipid peroxidation product 4-hydroxynonenal and of its metabolite 4-hydroxynonenoic acid on respiration of rat kidney cortex mitochondria.

In rat kidney cortex mitochondria, 4-hydroxynonenal inhibits state 3 respiration as well as uncoupled respiration at micromolar concentrations. The inhibition is more distinct for NAD-linked than for FAD-linked respiration. 4-Hydroxynonenal increases the state 4 respiration. It is assumed that 4-hydroxynonenal behaves like a decoupling agent. 4-Hydroxynonenal augments the inhibitory effect of 2,4-dinitrophenol observed at superoptimal concentrations. 4-Hydroxynonenal is metabolised by renal mitochondria, and 4-hydroxynonenoic acid is one of the metabolites generated. This metabolite is without effect on respiration at concentrations up to 50 microM. Therefore, the effect of 4-hydroxynonenal on respiration is not mediated by this fatty acid derivative formed during respiratory measurements.

Aldehydes↗
PubMed2000

Ribose 1,5-bisphosphate inhibits fructose-1,6-bisphosphatase in rat kidney cortex.

Fructose-1,6-bisphosphatase is one of the regulatory enzymes of gluconeogenesis in kidney cortex. The effect of ribose 1,5-bisphosphate on fructose-1,6-bisphosphatase purified from rat kidney cortex was studied. Rat kidney cortex, fructose-1,6-bisphosphatase exhibited hyperbolic kinetics with regard to its substrate, but the activity was inhibited by ribose 1,5-bisphosphate at nanomolar concentrations. The inhibitory effect of ribose 1,5-bisphosphate on the fructose-1,6-bisphosphatase was enhanced in the presence of AMP, one of the inhibitors of fructose-1,6-bisphosphatase. Fructose-2,6-bisphosphate, which is an inhibitor of fructose-1,6-bisphosphatase, inhibited rat kidney cortex fructose-1,6-bisphosphatase activities at a low concentration of fructose-1,6-bisphosphate but a high concentration of fructose-1,6-bisphosphate relieved fructose-1,6-bisphosphatase from fructose-2,6-bisphosphate-dependent inhibition. On the contrary, fructose-1,6-bisphosphate was not effective for the recovery of fructose-1,6-bisphosphatase from ribose 1,5-bisphosphate-dependent inhibition. These results suggest that ribose 1,5-bisphosphate is a potent inhibitor and is involved in the regulation of fructose-1,6-bisphosphatase in rat kidney cortex.

Animals↗
PubMed1969

The effects of dietary conditions and glycerol concentration on glycerol uptake by rat liver and kidney-cortex slices.

1. Glycerol utilization by rat liver and kidney-cortex slices was studied in an attempt to define factors that might be important in the regulation of glycerol utilization by these tissues in vivo; the formation of glucose from glycerol by kidney-cortex slices was also studied. 2. The rate of glycerol uptake by liver slices was not changed (in comparison with the normal fed control) by starvation (48hr.), feeding with a low-carbohydrate diet (4-8 days) or feeding with a diet containing 25% glycerol (up to 18 days). Similarly, starvation or a low-carbohydrate diet had no effect on uptake by kidney-cortex slices; however, feeding with the glycerol diet increased glycerol uptake by kidney-cortex slices. 3. The rates of glycerol uptake by slices from both tissues were increased on raising the glycerol concentration from 0.2mm to 2.5 or 5.0mm. 4. Starvation increased the conversion of glycerol into glucose by kidney-cortex slices, but there was no effect of the low-carbohydrate diet; the rate of glucose formation was increased by feeding with the 25%-glycerol diet and was proportional to the increase in glycerol uptake. The rate of glucose production by these slices was increased by raising the glycerol concentration in the incubation medium from 0.2mm to 1.0mm, but, except for the slices from animals receiving the 25%-glycerol diet, there was no effect above 1.0mm-glycerol. 5. The significance of plasma glycerol concentration in regulating glycerol uptake by these tissues is discussed.

Animals↗
PubMed1982

Glycine metabolism in rat kidney cortex slices.

When rat kidney cortex slices were incubated with glycine or [1-14C]glycine, after correcting for metabolite changes with control slices, product formation and glycine utilization fitted the requirements of the equation: 2 Glycine leads to ammonia + CO2 + serine. Evidence is presented that degradation via glyoxylate, by oxidation or transamination, is unlikely to have any significant role in kidney glycine catabolism. It is concluded that glycine metabolism in rat kidney is largely via glycine cleavage closely coupled with serine formation. 1-C decarboxylation and urea formation with glycine in rat hepatocyte suspensions were somewhat greater than decarboxylation or ammonia formation in kidney slices, showing that in the rat, potentially, the liver is quantitatively the more important organ in glycine catabolism. There was no evidence of ammonia formation from glycine with rat brain cortex, heart, spleen or diaphragm and 1-C decarboxylation was very weak.

Amino Acids↗
PubMedDate not supplied

Isolation and characterization of a microvascular fraction from rabbit kidney cortex.

Collagenasic dispersion of rabbit kidney cortex followed by centrifugation on discontinuous sucrose gradient, allowed the simultaneous isolation of a microvascular fraction and of glomerular and tubular fractions. The microvessels were characterized by an overall diameter of 22 micron and the presence of granular and smooth muscle cells. Measurement of cellular renin activity and the muscle specific enzyme creatine kinase showed that these vessels were arteriolar in nature and that they contained the preglomerular arterioles. The glomerular or tubular contamination rates were assessed by means of enzymatic markers. Thus, in the arterioles, potassium fluoride-resistant acid phosphatase was some 10 times lower than in the glomeruli. The specific tubular enzymes gamma-glutamyl-transpeptidase and alkaline phosphatase were about 20 times lower in the arterioles than in the tubular fraction. The possibility of obtaining these fractions may facilitate many types of study on renal hemodynamic and glomerulo-tubular feedback control.

Acid Phosphatase↗
PubMed1995

Expression of calcium-binding protein regucalcin mRNA in the kidney cortex of rats: the stimulation by calcium administration.

The expression of calcium-binding protein regucalcin mRNA in the kidney cortex of rats was investigated. The change of regucalcin mRNA levels was analyzed by Northern blotting using liver regucalcin complementary DNA (0.9 kb of open-reading frame). Regucalcin mRNA was expressed in the kidney cortex, and this expression was clearly increased by a single intraperitoneal administration of calcium chloride solution (5-15 mg Ca/100 g body weight) in rats; this increase was remarkable at 60-120 min after the administration. Thyroparathyroidectomy (TPTX) caused a slight decrease of regucalcin mRNA levels in the kidney cortex. However, the administration of calcium (10 mg/100 g) in TPTX rats produced a clear increase of regucalcin mRNA levels in the kidney cortex. The subcutaneous administration of calcitonin (10-100 MRC mU/100 g) or parathyroid hormone [1-34] (1-10 U/100 g) in TPTX rats which received calcium (10 mg/100 g) administration did not cause an appreciable alteration of regucalcin mRNA levels in the kidney cortex, suggesting that the mRNA expression is not stimulated by calcium-regulating hormones. The administration of trifluoperazine (TFP; 5 mg/100 g), an inhibitor of Ca2+/calmodulin action, completely blocked the expression of regucalcin mRNA stimulated by calcium administration. Now, calcium content in the kidney cortex was significantly elevated by a single intraperitneal administration of calcium (10 mg/100 g) in rats. The present study clearly demonstrates that the expression of regucalcin mRNA in the kidney cortex is stimulated by calcium administration in rats. This expression may be mediated through Ca2+/calmodulin action in the kidney cortex.

Adrenal Glands↗
PubMed1987

Latency of acid hydrolases in rat kidney cortex.

1. Some lysosomal populations in the rat kidney cortex appear to be mechanically weak and are readily disrupted by gentle homogenization, while other populations remain intact even after repeated homogenization. 2. Lysosomes in the rat kidney cortex appear to be resistant to hypertonic media but are readily disrupted under hypotonic conditions. 3. Lysosomes in rat kidney cortex are readily disrupted when incubated in isotonic sucrose at 37 degrees C. 4. Measurement of total and free activity of three acid hydrolases: N-acetyl-beta-D-glucosaminidase (NAG), acid beta-galactosidase and acid beta-glycerophosphatase, indicates that the latency of these enzymes is relatively low in the homogenate (10-29%) and the ML-fraction (14-42%), but high (60-95%) in the purified large lysosomes (protein droplets). 5. The latency of purified small lysosomes is relatively lower (30-60%) than that of large lysosomes, suggesting that small lysosome populations are relatively permeable to the acid hydrolase substrates. 6. Latency variations of acid hydrolases amongst subcellular fractions appear to reflect the heterogeneity of lysosomal populations present in the kidney cortical homogenate.

Acetylglucosaminidase↗
PubMed1999

Cadmium, mercury, and lead in kidney cortex of the general Swedish population: a study of biopsies from living kidney donors.

Cadmium, mercury, and lead concentrations were determined in deep-frozen kidney cortex biopsies taken from 36 living, healthy Swedish kidney donors (18 males and 18 females), who were 30-71 (mean 53) years of age. Information about occupation, smoking, the presence of dental amalgam, and fish consumption could be obtained for 27 of the donors. The samples (median dry weight 0.74 mg) were analyzed using inductively coupled plasma mass spectrometry, and the results were transformed to wet-weight concentrations. The median kidney Cd was 17 micrograms/g (95% confidence interval, 14-23 micrograms/g), which was similar in males and females. In 10 active smokers, the median kidney Cd was 24 micrograms/g, and in 12 who never smoked, it was 17 micrograms/g. The median kidney Hg was 0.29 micrograms/g, with higher levels in females (median 0.54 micrograms/g) than in males (median 0.16 micrograms/g). Subjects with amalgam fillings had higher kidney Hg (median 0.47 micrograms/g, n = 20) than those without dental amalgam (median 0.15 micrograms;g/g, n = 6), but kidney Hg was below the detection limit in some samples. Nearly half of the samples had kidney Pb below the detection limit. The median kidney Pb was estimated as 0. 14 micrograms/g. This is the first study of heavy metals in kidney cortex of living, healthy subjects, and the results are relatively similar to those of a few previous autopsy studies, indicating that results from autopsy cases are not seriously biased in relation to kidney metal concentrations in the general population. Cd concentrations in those who never smoked were relatively high, indicating considerable Cd intake from the diet in Sweden. The effect of dental amalgam on kidney Hg was as expected, although the reason for the difference in Hg levels between males and females is unclear.

Adult↗
PubMed1970

Gluconeogenesis in the kidney cortex. Effects of D-malate and amino-oxyacetate.

1. Rat kidney-cortex slices incubated with d-malate alone formed very little glucose. d-Malate, however, augmented gluconeogenesis from l-lactate and inhibited gluconeogenesis from pyruvate and l-malate. 2. d-Malate had little effect on the rate of the tricarboxylic acid cycle with or without other substrates added. 3. d-Malate inhibited the activity of the l-malate dehydrogenase in a high-speed-supernatant fraction from kidney cortex. 4. It was concluded that d-malate inhibited either the operation of the cytoplasmic l-malate dehydrogenase or malate outflow from the mitochondria in the intact kidney-cortex cell. This supports the hypothesis of Lardy, Paetkau & Walter (1965) and Krebs, Gascoyne & Notton (1967) on the role of malate as carrier for carbon and reducing equivalents in gluconeogenesis. 5. Gluconeogenesis from l-lactate in kidney-cortex slices was strongly inhibited by a low concentration (0.1mm) of amino-oxyacetate, whereas glucose formation from pyruvate, malate, aspartate and several other compounds was only slightly affected. 6. High concentrations of l-aspartate largely reversed the inhibition of gluconeogenesis from l-lactate caused by amino-oxyacetate. 7. Amino-oxyacetate inhibited strongly the glutamate-oxaloacetate transaminase in the 30000g supernatant fraction of a kidney-cortex homogenate. The presence of l-aspartate decreased the inhibition of the transaminase by amino-oxyacetate. 8. Detritiation of l-[2-(3)H]aspartate was inhibited by 90% during an incubation of kidney-cortex slices with l-lactate and amino-oxyacetate. 9. Low concentrations (10mum) of artificial electron acceptors such as Methylene Blue and phenazine methosulphate abolished most of the inhibition of gluconeogenesis from l-lactate by amino-oxyacetate. This is interpreted as an activation of net malate outflow from the mitochondria by-passing the inhibited transfer of oxaloacetate. 10. These findings support the concept that transamination to aspartate is involved in the transfer of oxaloacetate from mitochondria to cytosol required in gluconeogenesis from l-lactate.

Animals↗
PubMed1987

Metabolism of acetaldehyde in human and baboon renal cortex. Ethanol synthesis by isolated baboon kidney-cortex tubules.

Acetaldehyde (1-20 mM) was metabolized at high rates and in a dose-dependent manner in isolated human and baboon kidney-cortex tubules. Acetaldehyde removal was accompanied by a large accumulation of acetate in both human and baboon tubules. By contrast, a large synthesis of ethanol was observed only in baboon tubules. Consistent with the latter finding, ethanol was found to be metabolized at significant rates in baboon but not human tubules. In the tubules from both species, a significant fraction of the acetaldehyde removed was also completely oxidized to CO2 and H2O. These results suggest that, in both man and baboon, the kidneys participate in the in vivo metabolism of acetaldehyde; they also suggest that, in contrast with the human kidneys, the baboon kidneys contribute to the detoxication of circulating ethanol.

Acetaldehyde↗
PubMed1969

The fuel of respiration of rat kidney cortex.

1. In kidney-cortex slices from the well-fed rat, glucose (5mm) supplied 25-30% of the respiratory fuel; in the starved state, the corresponding value was 10%. These results are based on measurements of the net uptake of glucose and of the specific radioactivity of labelled carbon dioxide formed in the presence of [U-(14)C]-glucose. 2. Added acetoacetate (5mm) or butyrate (10mm) provided up to 80%, and added oleate (2mm) up to 50% of the fuel of respiration. The oxidation of endogenous substrates was suppressed correspondingly. 3. More [U-(14)C]oleate was removed by the tissue than could be oxidized by the amount of oxygen taken up; less than 25% of the oleate removed was converted into respiratory carbon dioxide and about two-thirds was incorporated into the tissue lipids. The rate of oleate incorporation into the neutral-lipid fraction was calculated to be equivalent to the rate of oxidation of endogenous fat, which provided the chief remaining fuel. 4. The contribution of endogenous substrates to the respiration (50%) in the presence of added oleate is taken to reflect either a high turnover rate of the endogenous neutral lipids (approx. half-life 2.5hr.) or a raised rate of lipolysis caused by the experimental conditions in vitro. 5. Added l-alpha-glycerophosphate (2.5mm) increased oleate incorporation into the neutral-lipid fraction by up to 40% (i.e. caused a net synthesis of triglyceride). 6. Lactate (2.5mm) added as sole substrate supplied 30% of the respiratory fuel, but with added oleate (2mm) lactate was converted quantitatively into glucose. Oleate stimulated the rate of gluconeogenesis from lactate by 45%. 7. The oxidation of both long-chain and short-chain even-numbered fatty acids was accompanied by ketone-body formation. Ketone-body synthesis from oleate, but not from butyrate, increased six- to seven-fold after 48hr. of starvation. The maximum rates of renal ketogenesis (80mumoles/hr./g. dry wt., with butyrate) were about 20% of the maximum rates observed in the liver (on a weight-for-weight basis) and accounted for, at most, 35% of the fatty acid removed. 8. dl-Carnitine (1.0mm) had no effect on the rates of uptake of acetate, butyrate or oleate or on the rate of radioactive carbon dioxide formation from [U-(14)C]oleate, but increased ketone-body formation from oleate by more than 100%. Ketone-body formation from butyrate was not increased. 9. There is evidence supporting the assumption that there are cells in which gluconeogenesis and ketogenesis occur together, characterized by equal labelling of [U-(14)C]oleate and the ketone bodies formed, and other cells that oxidize fat and do not form ketone bodies. 10. Inhibitory effects of unlabelled acetoacetate on the oxidation of [1-(14)C]butyrate and of unlabelled butyrate on [4-(14)C]acetoacetate oxidation show that fatty acids and ketone bodies compete as fuels on the basis of their relative concentrations. 11. The pathway of ketogenesis in renal cortex must differ from that of the liver, as beta-hydroxy-beta-methylglutaryl-CoA synthetase is virtually absent from the kidney. In contrast with the liver the kidney possesses 3-oxo acid CoA-transferase (EC 2.8.3.5), and the ready reversibility of this reaction and that of thiolase (EC 2.3.1.9) provide a mechanism for ketone-body formation from acetyl-CoA. This mechanism may apply to extrahepatic tissues generally, with the possible exception of the epithelium of the rumen and intestines.

Acetoacetates↗