Kinetics of the early subcellular distribution of cadmium in rat hepatocytes

Knowledge of the kinetics of cell distribution in vascular beds will help optimize engraftment of transplanted hepatocytes. To noninvasively localize transplanted cells in vivo, we developed conditions for labeling rat hepatocytes with 99mTc–pertechnetate. The incorporated 99mTc was bound to intracellular proteins and did not impair cell viability. When 99mTc hepatocytes were intrasplenically injected into normal rats, cells entered liver sinusoids with time–activity curves demonstrating instantaneous cell translocations. 99mTc activity in removed organs was in liver or spleen, and lungs showed little activity. However, when cells were intrasplenically transplanted into rats with portasystemic collaterals, 99mTc appeared in both liver sinusoids and pulmonary alveolar capillaries. To further localize cells, we transplanted DPPIV+ F344 rat hepatocytes into syngeneic DPPIV – recipients. Histochemical staining for DPPIV activity demonstrated engraftment of intrasplenically transplanted cells in liver parenchyma. In contrast, when 99mTc hepatocytes were injected into a peripheral vein, cells were entrapped in pulmonary capillaries but were subsequently broken down with redistribution of 99mTc activity elsewhere. Intact DPPIV+ hepatocytes were identified in lungs, whereas only cell fragments were present in liver, spleen, or kidneys. These findings indicate that although the pulmonary vascular bed offers advantages of easy accessibility and a relatively large capacity, significant early cell destruction is an important limitation.

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Kinetics of taurocholate efflux from freshly isolated suspensions and primary cultures of rat hepatocytes

Hepatology ◽

10.1002/hep.1840110507 ◽

1990 ◽

Vol 11 (5) ◽

pp. 750-756 ◽

Cited By ~ 8

Author(s):

Veerapol Kukongviriyapan ◽

Neill H. Stacey

Keyword(s):

Primary Cultures ◽

Rat Hepatocytes ◽

Kinetics Of

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Age-dependence in capacity-limited uptake kinetics of propranolol by isolated rat hepatocytes

Biochemical Pharmacology ◽

10.1016/0006-2952(86)90174-7 ◽

1986 ◽

Vol 35 (16) ◽

pp. 2677-2681 ◽

Cited By ~ 3

Author(s):

Iwamoto Kikuo ◽

Watanabe Jun ◽

Satoh Mariko

Keyword(s):

Rat Hepatocytes ◽

Uptake Kinetics ◽

Age Dependence ◽

Isolated Rat Hepatocytes ◽

Kinetics Of ◽

Isolated Rat

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Evidence that Ca2+-release-activated Ca2+ channels in rat hepatocytes are required for the maintenance of hormone-induced Ca2+ oscillations

Biochemical Journal ◽

10.1042/bj20021671 ◽

2003 ◽

Vol 370 (2) ◽

pp. 695-702 ◽

Cited By ~ 27

Author(s):

Roland B. GREGORY ◽

Gregory J. BARRITT

Keyword(s):

High Selectivity ◽

Rat Hepatocytes ◽

Isolated Hepatocytes ◽

Cation Channels ◽

Isolated Rat Hepatocytes ◽

Pharmacological Agents ◽

Crac Channels ◽

Kinetics Of ◽

Ca2 Channels

Store-operated Ca2+ channels in liver cells have been shown previously to exhibit a high selectivity for Ca2+ and to have properties indistinguishable from those of Ca2+-release-activated Ca2+ (CRAC) channels in mast cells and lymphocytes [Rychkov, Brereton, Harland and Barritt (2001) Hepatology 33, 938—947]. The role of CRAC channels in the maintenance of hormone-induced oscillations in the cytoplasmic free Ca2+ concentration ([Ca2+]cyt) in isolated rat hepatocytes was investigated using several inhibitors of CRAC channels. 2-Aminoethyl diphenylborate (2-APB; 75μM), Gd3+ (1μM) and 1-{β-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl}-1H-imidazole hydrochloride (SK&F 96365; 50μM) each inhibited vasopressin- and adrenaline (epinephrine)-induced Ca2+ oscillations (measured using fura-2). The characteristics of this inhibition were similar to those of inhibition caused by decreasing the extracellular Ca2+ concentration to zero by addition of EGTA. The effect of 2-APB was reversible. In contrast, LOE-908 {(R,S)-(3,4-dihydro-6,7-dimethoxy-isochinolin-1-yl)-2-phenyl-N,N-di[2-(2,3,4-trimethoxyphenyl)ethyl]acetamidemesylate}(30μM), used commonly to block Ca2+ inflow through intracellular-messenger-activated, non-selective cation channels, did not inhibit the Ca2+ oscillations. In the absence of added extracellular Ca2+, 2-APB, Gd3+ and SK&F 96365 did not alter the kinetics of the increase in [Ca2+]cyt induced by a concentration of adrenaline or vasopressin that induces continuous Ca2+ oscillations at the physiological extracellular Ca2+ concentration. Ca2+ inflow through non-selective cation channels activated by maitotoxin could not restore Ca2+ oscillations in cells treated with 2-APB to block Ca2+ inflow through CRAC channels. Evidence for the specificity of the pharmacological agents for inhibition of CRAC channels under the conditions of the present experiments with hepatocytes is discussed. It is concluded that Ca2+ inflow through CRAC channels is required for the maintenance of hormone-induced Ca2+ oscillations in isolated hepatocytes.

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A mathematical model of the kinetics of 5-fluorouracil and its catabolites in freshly isolated rat hepatocytes

Biochemical Pharmacology ◽

10.1016/0006-2952(84)90688-9 ◽

1984 ◽

Vol 33 (17) ◽

pp. 2727-2732 ◽

Cited By ~ 10

Author(s):

France Mentre ◽

Jean-Louis Steimer ◽

Jean-Pierre Sommadossi ◽

Robert B. Diasio ◽

Jean-Paul Cano

Keyword(s):

Mathematical Model ◽

Rat Hepatocytes ◽

Isolated Rat Hepatocytes ◽

Kinetics Of ◽

Freshly Isolated Rat Hepatocytes ◽

Isolated Rat

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Intracellular and transcellular transport of secretory component and albumin in rat hepatocytes.

The Journal of Cell Biology ◽

10.1083/jcb.97.5.1582 ◽

1983 ◽

Vol 97 (5) ◽

pp. 1582-1591 ◽

Cited By ~ 71

Author(s):

E S Sztul ◽

K E Howell ◽

G E Palade

Keyword(s):

Membrane Proteins ◽

Golgi Complex ◽

Rat Hepatocytes ◽

Secretory Component ◽

Bile Canaliculus ◽

Sds Page ◽

Iga Antibody ◽

Co Precipitation ◽

Kinetics Of

The intra- and transcellular transports of hepatic secretory and membrane proteins were studied in rats in vivo using [3H]fucose and [35S]cysteine as metabolic precursors. Incorporated radioactivity in plasma, bile, and liver subcellular fractions was measured and the labeled proteins of the Golgi complex, bile, and plasma were separated by SDS PAGE and identified by fluorography. 3H-radioactivity in Golgi fractions peaked at 10 min postinjection (p.i.) and then declined concomitantly with the appearance of labeled glycoproteins in plasma. Maximal secretion of secretory fucoproteins from Golgi occurred between 10 and 20 min p.i. In contrast, the clearance of labeled proteins from Golgi membrane subfractions occurred past 30 min p.i., indicating that membrane proteins leave the Golgi complex at least 30 min later than the bulk of content proteins. A major 80,000-dalton form of secretory component (SC) was identified in the bile by co-precipitation with (IgA)2 by an anti-IgA antibody. An antibody (raised in rabbit) against the biliary 80,000-dalton peptide recognized two larger forms (116,000 and 94,000 dalton), presumably precursors, in Golgi membranes. A comparative study of kinetics of transport of 35S-SC and 35S-albumin showed that albumin peaked in bile at approximately 45 min p.i., whereas the SC peak occurred at 80 min p.i., suggesting that the transit time differs for plasma and membrane proteins that are delivered to the bile canaliculus.

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