Pharmacokinetics of cocaine in pregnancy and effects on fetal maturation.
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Abnormalities, Drug-Induced↗
Biomedical subjects
R C Wiggins
Publications and source records attributed to R C Wiggins.
Tissue factor expression in endothelial cell/monocyte cocultures stimulated by lipopolysaccharide and/or aggregated IgG. Mechanisms of cell:cell communication.
A human umbilical vein endothelial cell (EC)/monocyte (MC) coculture system was used to dissect cell:cell interactions associated with production of procoagulant activity (PCA) in response to two common stimuli of intravascular coagulation in vivo (LPS and immune complexes). We found that the presence of MC at a ratio of 1 MC:10 EC increased the sensitivity of EC to LPS by 4 logs and the maximal response approximately 20-fold. Aggregated IgG alone did not stimulate the system, but in the presence of small amounts of LPS (1 to 10 ng/ml) aggregated IgG was a powerful stimulus. More than 90% of the PCA was tissue factor as shown by clotting studies and mRNA analysis. PCA was not produced by either cell alone under the conditions of study, but was produced in large amounts when the EC and MC were cocultured. The supernatant from the coculture stimulated virgin EC, but not MC, to synthesize tissue factor. The major factor in the supernatant was IL-1 beta as shown by measuring IL-1 beta, IL-1 alpha, and TNF-alpha in supernatants and by blocking the production of PCA by preincubation of supernatants with anti-cytokine antibodies. Small amounts of TNF-alpha were present in the supernatant but anti-TNF-alpha did not inhibit PCA production. Studies using recombinant cytokines established that IL-1 beta was the most potent of the cytokines tested, that cytokines potentiated each other, and that the results could be explained in quantitative terms by the amounts of IL-1 beta measured. These data emphasize that cell:cell interactions are likely to modulate procoagulant events in vivo in the presence of both LPS and immune complexes, and that IL-1 beta may be an important cytokine in these events.
Antigen-Antibody Complex↗
Effect of culture conditions on PLP and MAG gene expression in rat glioma C6 cells.
The effects of culture conditions on the expression of myelin-specific genes, i.e. proteolipid protein (PLP) and myelin-associated glycoprotein (MAG) in rat glioma C6 cells was studied. Early passage (40-46) cells had higher steady-state level of PLP- and MAG-specific mRNA than late (100) passage cells when grown in defined (serum-free) medium. The PLP gene expression was increased whereas the MAG gene expression was reduced in the presence of 10% fetal calf serum in either passage. The level of both PLP- and MAG-specific messages was also directly related to the cell density indicating cell contact-induced stimulation of the gene expression. Furthermore, the cells apparently secrete factors into the medium, which upregulate the gene expression in autocrine fashion. The results also indicate a dissimilarity of regulatory mechanisms involved in the expression of the PLP and MAG genes.
Animals↗
Differential regulation of myelin gene expression in SV40 T antigen-transfected rat glioma C6 cells.
Rat glioma C6 cells were stably transfected with a pSV3-neo plasmid containing SV40 T antigen gene, and geniticin-resistant transfectants (designated C6T cells) were cloned. The C6T cells grew as well-defined foci of cells showing squamous or irregular morphology. The doubling time for transfected cells was reduced by approximately 40% as compared to control C6 cells. The transfection with T-antigen also affected the expression of genes coding for structural myelin proteins and for myelin-associated enzymes. The steady-state level of proteolipid protein (PLP)-specific mRNA in C6T cells was 44% lower than in parental C6 cells. On the other hand, the transfection upregulated the expression of myelin-associated glycoprotein (MAG) by 153%. The activity of 2':3' cyclic AMP phosphodiesterase (CNP) was increased by approximately 80% in the C6T cells as compared to untransfected, control cells. The activity of calcium-activated neutral proteinase (CANP) was also significantly elevated in the transfectants by approximately 50% and 220% for millimolar and micromolar form respectively. The results indicate that T antigen affects the expression of myelin genes, although, individual genes appear to be differently regulated implying the existence of several independent regulatory mechanisms.
3',5'-Cyclic-AMP Phosphodiesterases↗
Turbidity as a measure of particulate subcellular fraction yield.
Turbidity measurement, as an estimate of the concentration of a particulate subcellular membrane fraction, is an effective alternative to protein assay. As exemplified by purified myelin membrane the technique is fast, accurate, and consumes no sample, giving it certain advantages over protein assay in some applications.
Animals↗
Generation of high efficiency, single-stranded DNA hybridization probes by PCR.
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Animals↗
Consequences of glomerular injury. Glomerular crescent formation.
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Animals↗
Development under the influence of cocaine. I. A comparison of the effects of daily cocaine treatment and resultant undernutrition on pregnancy and early growth in a large population of rats.
After administering cocaine to pregnant and lactating dams in oral dosages ranging from 5 to 90 mg/kg/day, we observed a slight increase in fatalities starting at 60 mg/kg/day, followed by a sharp rise fatalities at higher dosages. Therefore, a dosage near 60 mg/kg/day by the oral route appears to mark a useful threshold between highly lethal dosages and an acceptable, sublethal dosage for chronic studies of pregnant rats. At 60 mg/kg/day, there was a marginal trend toward less weight gain in the cocaine-treated dams during pregnancy, followed by a much more pronounced lag in weight recovery following parturition. Neither prematurity nor any reduction in litter sizes and birth weights was consistently observed at dosages below 90 mg/kg/day; however, poor maternal care was evident when the dams received dosages of 80-90 mg/kg/day, producing a very high death rate in the neonatal offspring. Internal bleeding (intracranial and subcutaneous) was also observed in three neonates whose dams received cocaine at rates of 60-90 mg/kg/day, confirming a similar clinical observation and indicating a direct action of cocaine toxicity on the fetus. Although fetal growth and development were not significantly altered by administering the pregnant dams 60 mg/kg/day, there was a higher death rate in the offspring during the initial 24 hr after delivery. Weight gain appeared transiently retarded early in the suckling period, although similar growth retardation was observed in the offspring of pair-fed controls. These results indicate that the dam's undernourishment contributes much to the early growth retardation resultant from cocaine administration. The most striking effect of cocaine on the offspring, after considering undernourishment, appears to be an increased mortality in the neonatal period (60 mg/kg/day and higher), apparently resulting from poor maternal care. The greatest risk of all was the death of the dam at any point beginning with the second administration of cocaine at 60 mg/kg/day and increasing precipitously at any higher dosage.
Aging↗
Development under the influence of cocaine. II. Comparison of the effects of maternal cocaine and associated undernutrition on brain myelin development in the offspring.
Pregnant and lactating Long-Evans rats were treated daily with oral cocaine at a dosage rate of 60 mg/kg/day, which is the highest dosage tolerated during chronic treatment. Brain myelin concentrations were compared in the offspring during early myelination (day 15) and peak myelination (day 20). Body and brain weights in the offspring of cocaine-treated and pair-fed dams were transiently (but insignificantly) retarded, and by day 20 brain weights of the normal controls, cocaine-exposed, and pair-fed pups were the same (1.36 +/- 0.01-1.35 +/- 0.01 g). Similarly, specific myelin yields in the offspring of pair-fed dams were retarded by no more than 1-2% of the myelin concentrations obtained in normal controls, which is consistent with studies showing that such minimal growth retardation would not be expected to produce hypomyelination. In contrast, myelin concentrations from the brains of cocaine-exposed pups were reduced about 10%. In addition, cross-fostering indicated that the fetal period of cocaine exposure presents a greater risk to postnatal myelination than exposure during the suckling period, which is the reverse of the vulnerability resultant from undernourishment. Thus, the hypomyelination observed in the offspring of cocaine-treated dams indicates a toxic effect of cocaine acting directly on the developing offspring.
Aging↗
Microiontophoresis of cocaine, desipramine, sulpiride, methysergide, and naloxone in habenula and parafasciculus.
The effects of microiontophoretically applied cocaine, desipramine (DES), sulpiride (SUL), methysergide (METH), and naloxone (NAL) on the responses of physiologically identified single neurons in the habenula (Hab) and parafasciculus thalami nucleus (PF) were examined in rats. Three cell types were identified in both nuclei on the basis of the responses obtained following noxious stimulation that were classified as "nociceptive-on," "nociceptive-off," and "nonnociceptive" cells. Administration of cocaine generally resulted in a decrease in the firing rate of nociceptive-on and nonnociceptive neurons in both Hab and PF. In contrast, cocaine generally induced an excitation in the baseline firing of the nociceptive-off cells. Cocaine application concomitant with noxious stimulation prevented the evoked responses of the nociceptive-on and the nociceptive-off cells. DES, when applied alone, was found to induce excitation in neuronal discharge of all three cell types in both sites. Combined application of cocaine with DES resulted in no observable change in discharge frequency for the nociceptive-on and nonnociceptive cells, while inducing an additive excitatory effect on the nociceptive-off cells. SUL, in contrast, induced no observable effect on baseline firing when given alone, yet consistently antagonized cocaine-induced effects on all three cell types. Finally, METH and NAL induced no effects on baseline firing or cocaine-induced modifications in neuronal discharge frequency.
Animals↗
Effects of microiontophoretic application of cocaine, alone and with receptor antagonists, upon the neurons of the medial prefrontal cortex, nucleus accumbens and caudate nucleus of rats.
The spontaneous extracellular electrical activity of 102 neurons, within the caudate nucleus (CN), medial prefrontal cortex (MPC), nucleus accumbens (NAc) and a control site, the lateral thalamic nucleus (LT), was studied. Cocaine depressed spontaneous activity in the majority of the cells studied from all regions except the lateral thalamus. Desipramine, which has been used clinically for the treatment of withdrawal of cocaine, also depressed neuronal activity in the caudate nucleus. In addition, of the three receptor antagonists tested, sulpiride, methysergide and naloxone, only the dopamine antagonist (sulpiride) affected cocaine-induced neuronal responses. This study further emphasizes the emerging importance of midbrain dopaminergic systems in the pharmacological effects of this important drug of abuse.
Animals↗
Tissue factor production by cultured rat mesangial cells. Stimulation by TNF alpha and lipopolysaccharide.
Fibrin formation plays an important role in glomerular injury. We therefore examined the procoagulant signal produced by cultured rat mesangial cells. Actively growing mesangial cells produced procoagulant activity (PCA) that was present in intact cells (surface-associated), was inhibitable by cyclohexamide and which, by clotting assay, had the characteristics of tissue factor. This PCA decreased with incubation of cells in serum-deprived medium. Incubation with bacterial lipopolysaccharide (LPS) and tumor necrosis factor (TNF alpha) induced increased detectable tissue factor by mesangial cells within two hours which was maximal by four hours. We conclude that quiescent mesangial cells produce a small amount of tissue factor-like procoagulant activity, and that this PCA can be stimulated by incubation with TNF alpha, LPS or when cells are actively growing in high serum medium. Therefore mesangial cells have the capability of contributing to fibrin formation during inflammatory glomerular injury or sepsis.
Animals↗
Tumor necrosis factor production and accumulation of inflammatory cells in the corpus luteum of pseudopregnancy and pregnancy in rabbits.
The potential involvement of macrophages, T lymphocytes, and the cytokine tumor necrosis factor (TNF) in regression of the corpus luteum was investigated at different stages of pseudopregnancy and pregnancy by use of immunocytochemical methods and a TNF bioassay. Few macrophages (11 +/- 6 per high power field of 8-microns frozen sections of corpus luteum, Day 10 of pseudopregnancy) were observed until the very end of pseudopregnancy, when the number of macrophages increased greatly (176 +/- 42 per high power field, Day 19 of pseudopregnancy). Pregnancy, of 32 days duration, delayed large-scale macrophage accumulation until 3 days after parturition (154 +/- 30 per high power field). Low TNF activity (approximately 1.0 U/mg protein) was detected in incubations of luteal tissue at all stages; in response to lipopolysaccharide, TNF values in medium increased 10- to 30-fold at times of luteal regression and macrophage accumulation (1 day postpartum and Day 19 of pseudopregnancy). Class II-positive T lymphocytes were observed in luteal tissue, but unlike macrophages, the number of lymphocytes did not increase at the time of regression of the corpus luteum. These data are consistent with the hypothesis that involution of the corpus luteum is promoted through the interactions of inflammatory cells and action of TNF, although the action of TNF has not been determined in this luteal tissue. Through unknown mechanisms, pregnancy postpones the accumulation of macrophages in the corpus luteum, in association with the prolongation of luteal function until the time of parturition.
Animals↗
Moderate protection of renal function and reduction of fibrosis by colchicine in a model of anti-GBM disease in the rabbit.
A rabbit model of renal glomerulosclerosis induced by anti-glomerular basement membrane antibody was used to determine whether colchicine would protect renal function and reduce fibrosis. Initial studies established the time course of renal function changes and fibrosis. Colchicine at a dose of 0.02 to 0.04 mg/kg per day injected ip was begun at day 4 when injury had been initiated, and the experiment was ended at day 21 when fibrotic changes were established. Colchicine significantly reduced the rise in serum creatinine (serum creatinine = 2.7 +/- 0.3 mg% in vehicle-treated animals versus 1.8 +/- 0.1 mg% in colchicine-treated animals) and interstitial fibrosis (fibrosis score = 2.6 +/- 0.2 in vehicle-treated versus 1.5 +/- 0.2 in colchicine-treated animals). Colchicine treatment did not significantly affect weight, anti-guinea pig immunoglobulin level, % fibrocellular crescents formed, hydroxyproline per gram (dry weight) in tissue, or urine protein: creatine ratio. Regression analysis was performed to examine the interrelationships between variables for all animals and the effect of colchicine on pairs of variables. No clear-cut site of colchicine action could be identified. These data show that colchicine, in doses that could be used in humans, protected renal function by about 25% and reduced interstitial fibrosis in a model of severe crescentic nephritis.
Animals↗
Cocaine interaction with sulpiride, methysergide, naloxone and desipramine: neurophysiological effects of mesolimbic and neostriatal neuronal activity.
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Animals↗
Analysis of alpha 1 (I) procollagen alpha 1 (IV) collagen, and beta-actin mRNA in glomerulus and cortex of rabbits with experimental anti-glomerular basement membrane disease. Evidence for early extraglomerular collagen biosynthesis.
Renal cortical and glomerular mRNA for alpha 1 (I) and alpha 1 (IV) collagen were measured by filter hybridization during experimental anti-glomerular basement membrane disease in the rabbit. The abundance of alpha 1 (IV) mRNA was 5 times greater in total RNA isolated from glomeruli as compared with whole renal cortex from normal rabbits. In contrast, there was no difference in the relative amounts of alpha 1 (I) procollagen mRNA in these two fractions. Four days after the administration of anti-glomerular basement membrane antisera, a time histologically characterized by glomerular inflammatory cell infiltration without crescent formation, beta-actin mRNA were increased 17-fold in glomeruli and 4-fold in whole renal cortex. Renal cortical mRNA for alpha 1 (I) and alpha 1 (IV) were increased 7-fold (p = 0.07) and 9-fold (p less than 0.05), respectively compared with normal rabbit kidney cortex. In contrast, there was no significant difference in the abundance of these mRNA in glomeruli at day 4. By day 7, cortical alpha 1 (I) and alpha 1 (IVP mRNA had increased 17- and 10-fold, respectively, and these transcripts had increased 13- and 7-fold in glomeruli. Cortical alpha 1 (I) mRNA remained elevated for 35 days. These data show that large changes in collagen mRNA levels occur early in this model of crescentic nephritis in the rabbit, and that extraglomerular collagen mRNA accumulates very rapidly when glomerular inflammation occurs. Extraglomerular collagen synthesis associated with intraglomerular inflammation may help to explain the common association of interstitial fibrosis with glomerulonephritis, particularly in the periglomerular area.
Actins↗
Pharmacokinetics of cocaine: basic studies of route, dosage, pregnancy and lactation.
As a preface to the pharmacokinetic analysis of cocaine in pregnant and lactating rats (using oral administration of drug), young Long-Evans rats were used to compare the relative concentrations of cocaine in blood, brain, and liver after administering cocaine by iv or oral routes. Cocaine and its metabolites were determined using 3H-cocaine as a tracer, followed by homogenization and solvent extraction of tissues, and quantitative analysis by HPTLC and LSC. From 30 min postinjection to several hrs later, the concentration of cocaine was higher in brain (3-4 fold) and liver (3-5 fold) than in blood, using the iv route. Using the oral route, the concentration in brain was 2-3 fold higher than in blood, and in liver, 10-20 fold higher. The metabolites of cocaine were largely excluded from entry into brain tissue, whereas the accumulation of metabolites in liver was typically an order of magnitude higher, or more, than in blood (iv or oral route). The ratio of cocaine to metabolites increased in all three tissues, as the dosage increased, indicating that more and more of an administered dose actually reaches the tissues as cocaine as the dosage level increases. During the period from 30 to 90 min following the administration of cocaine to pregnant dams, cocaine appeared in fetal brain at a rate of 50-90% of the concentration in the dam's brain (presumably because of the lower lipid content in fetal brain compared to adult), but still at a rate of 109-151% of the concentration in the dam's blood. Cocaine is sufficiently stable in milk to assume that any cocaine entering breast milk from the blood stream will be available to the suckling infant, and after administering radioactive cocaine to lactating dams, the milk/blood ratio for cocaine averaged 7.8. These data indicate that both the fetus and suckling infant are at considerable risk from cocaine use by the mother.
Administration, Oral↗
The appended curve technique for deconvolutional analysis--method and validation.
Deconvolutional analysis (DCA) is useful in correction of organ time activity curves (response function) for variations in blood activity (input function). Despite enthusiastic reports of applications of DCA in renal and cardiac scintigraphy, routine use has awaited an easily implemented algorithm which is insensitive to statistical noise. The matrix method suffers from the propagation of errors in early data points through the entire curve. Curve fitting or constraint methods require prior knowledge of the expected form of the results. DCA by Fourier transforms (FT) is less influenced by single data points but often suffers from high frequency artifacts which result from the abrupt termination of data acquisition at a nonzero value. To reduce this artifact, we extend the input (i) and response curves to three to five times the initial period of data acquisition (P) by appending a smooth low frequency curve with a gradual taper to zero. Satisfactory results have been obtained using a half cosine curve of length 2-3P. The FTs of the input and response I and R, are computed and R/I determined. The inverse FT is performed and the curve segment corresponding to the initial period of acquisition (P) is retained. We have validated this technique in a dog model by comparing the mean renal transit times of 131I-iodohippuran by direct renal artery injection to that calculated by deconvolution of an intravenous injection. The correlation was excellent (r = 0.97, P less than 0.005). The extension of the data curves by appending a low frequency "tail" before DCA reduces the data termination artifact. This method is rapid, simple, and easily implemented on a microcomputer.(ABSTRACT TRUNCATED AT 250 WORDS)
Animals↗