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Biomedical subjects

K W Lieberman

Publications and source records attributed to K W Lieberman.

At least 19 recordsLinked to original sources
PubMed1998

Dextro-naloxone counteracts amphetamine-induced hyperactivity.

The locomotor stimulating effect of d-amphetamine in mice was counteracted by the administration of l-naloxone [(-)-naloxone], a known opiate receptor antagonist. Mice injected with amphetamine reached a peak locomotor activity within 30 min. When treated simultaneously with amphetamine and l-naloxone, these subjects showed low motility. Furthermore, when mice were treated not with l-naloxone but with its mirror image, d-naloxone [(+)-naloxone], a compound that by itself does not antagonize opiates and does not affect spontaneous motility, they showed no amphetamine-induced hyperactivity. The finding that an enantiomer of naloxone, with no opiate antagonist activity, is able to block the excitatory action of amphetamine, suggests the existence of a hitherto unknown mechanism of counteracting some of the effects of stimulants and euphoriants like amphetamine and cocaine.

Amphetamine↗
PubMed1996

Prevention of cocaine-induced hyperactivity by a naloxone isomer with no opiate antagonist activity.

Dextro-naloxone [(+)-naloxone], an isomer with almost no opiate antagonist activity and no effect on spontaneous locomotor activity, can reduce cocaine-induced hyperactivity in mice. The classical opiate antagonist, levo-naloxone [(-)-naloxone], is known to counteract the excitatory motor effects of amphetamine and cocaine, but it has been tacitly assumed that this action of levo-naloxone is dependent on its ability to antagonize endogenous opioids. Our finding that a naloxone isomer with little or no opioid antagonist activity is also able to inhibit the cocaine effect on spontaneous motility, calls for a reconsideration of this assumption.

Animals↗
PubMed1987

Platelet MAO activity in geriatric patients with depression and dementia.

The authors studied platelet MAO activity in psychiatrically hospitalized geriatric patients with depression and dementia. Platelet MAO activity was higher in demented patients with and without depression and in depressed patients with reversible dementia than in nondemented depressed patients. The data suggest that abnormally high platelet MAO activity may reflect a predisposition to the development of a dementia syndrome.

Aged↗
PubMed1986

Aberrant parenting and delayed offspring development in rats exposed to lithium.

Natural lithium (Li) salts, including those used routinely in manic depressive illness, consist of two stable nonradioactive isotopes: lithium-7 (Li-7) (92.6%) and lithium-6 (Li-6) (7.4%). Female rats (3 months old) were treated with either Li-7 chloride or Li-6 chloride or were untreated prior to and during gestation and lactation. Birth weights were lower for Li-treated animals than for normal pups. Maternal behavior of all Li-treated mothers was altered. Li-7 mothers ignored their pups and nursed them infrequently. Li-6 mothers groomed and nursed their pups more often than normal mothers. All pups showed delays in development, especially in the maturation of depth perception. Although Li-6-treated dams were over-protective mothers, their offspring showed longer developmental delays than those of Li-7-treated offspring.

Animals↗
PubMed1985

Erythrocyte differentiation of naturally occurring isotopic lithium abundances.

Lithium is effective in the treatment of mania. There are two naturally occurring stable lithium isotopes, Li-7 (92.6%) and Li-6 (7.4%). Usually there is little differentiation between isotopes of an element, but chemical and behavioural data suggest dissimilarities exist between lithium isotopes. Results are now reported indicating that a group of manic patients given lithium chloride were able to differentiate Li-6 from Li-7 at the membrane level. Blood samples were drawn, erythrocytes separated from plasma and the isotopic abundances of Li-6 and Li-7 determined by atomic absorption spectrophotometry. The ratio of abundances of Li-6 in the erythrocyte and plasma was 1.274 indicating the erythrocyte membrane had the in vivo capability of isotope fractionation.

Adult↗
PubMed1984

Platelet MAO activity in primary degenerative dementia.

Platelet MAO activity was studied in 24 patients with primary degenerative dementia and 20 normal elderly controls. Demented patients had significantly higher platelet MAO activity than did controls. The increase was greater than that reported to occur in normal aging.

Age Factors↗
PubMed1983

Platelet MAO activity in alcoholic patients and their first-degree relatives.

The authors studied 49 alcoholic in patients in remission, 18 first-degree relatives of 10 of these alcoholics, and 25 normal control subjects. Alcoholic patients had significantly lower platelet monoamine oxidase (MAO) activity than control subjects. There was an inverse relationship between platelet MAO levels in the alcoholic patients and prevalence of reported alcoholism in their first-degree relatives. First-degree relatives of alcoholics had lower platelet MAO activity than control subjects. The data suggest a relationship between low platelet MAO activity and predisposition to familial alcoholism.

Adult↗
PubMed1982

Lithium toxicology: effect of isotopic composition on lethality and behavior.

Naturally occurring lithium consists largely of the stable lithium-7 isotope but it contains 7.6% of a second stable isotope, lithium-6. Biological effects of these two isotopes were not identical. When administered in isotopically pure form, the chloride of lithium-6 was more toxic after acute intake than the chloride of pure lithium-7:its LD in Swiss-Webster mice was 13.2 mEq/kg as opposed to 15.9 mEq/kg for the salt of the heavier isotope and 14.9 mEq/kg for that of the natural mixture of the two isotopes. A single injection of one or the other pure isotope in a constant dose, 14.5 mEq/kg led to a 90% mortality in mice given lithium-6 but only 10% in mice given lithium-7. Side effects such as hypoactivity, ataxia, intense perspiration and diarrhea appeared within 10 min after administration of toxic doses of lithium-6 but more gradually after lithium-7. The differences between the isotopes in toxicity and rate of appearance of effects on spontaneous motor activity were significant at the p less than 1% level.

Animals↗
PubMed1982

Lithium ratio and maintenance treatment response.

Erythrocyte/plasma lithium ratios were determined in 41 polar manic depressive outpatients maintained on lithium for a mean of 64 months. Sixteen patients experienced affective episodes requiring additional pharmacologic intervention during periods when their plasma lithium averaged 0.7 meq/l or above for at least 3 preceding months and they were on no concurrent medication known to induce depression or mania. These patients considered to be a homogeneous group of non-responders to lithium, had a mean lithium ratio of 0.50 (range 0.15-1.16). Seven patients experienced affective symptoms at plasma levels below 0.7 meq/1 and/or while taking concurrent medication known to induce affective symptoms, and therefore could not be categorized clinically as lithium non-responders or responders. Eighteen remaining patients, who had no affective episodes during lithium maintenance, were found to have a mean erythrocyte/plasma ratio of 0.52 (range 0.19-1.05). This latter group of apparent responders should be considered heterogeneous in that it may include spontaneous remitters. The difference in mean ratios between the non-responder group and the apparent responder group was not statistically significant. These findings support the contention that the erythrocyte/plasma lithium ratio does not correlate with response of bipolar outpatients to maintenance lithium.

Bipolar Disorder↗
PubMed1982

Stable isotopes of lithium: in vivo differential distribution between plasma and cerebrospinal fluid.

Stable and radioactive isotopes of an element have been utilized to study a variety of complex phenomena including metabolic pathways and enzyme reactions. It is generally assumed that isotopes of an element are not treated in a differential manner. Nevertheless we have demonstrated that the two stable isotopes of lithium (Li), one of mass 6 and the other with a mass of 7, are differentially taken up by red blood cells with 6-8% higher quantities of 6-lithium (6Li) being accumulated. We report here on the in vivo pharmacokinetics of Li isotopes. Nineteen adult cats were given a single dose of either 6LiCl by gastric intubation (1 meq/kg) and 2 weeks later the treatment was crossed. Plasma concentrations of the two Li isotopes were determined. In another series of studies 19 adult cats were given either 6LiCl or 7LiCl by intubation, cerebrospinal fluid (CSF) and blood samples were collected simultaneously and isotropic Li concentrations of the spinal fluid and plasma were determined. The average plasma concentration of 6Li was higher than 7-lithium (7Li) between 2 and 9 hr postadministration. The elimination curve for both isotopes had an initial fast and later slow component. For the slow component 6Li had an average half-life of 12.9 and 7Li 15.9 hr. Comparison of the CSF/plasma ratio for 6Li and for 7Li indicated that the ratios were higher for 6Li than 7Li 2-6 hr after administration. These data suggest that factors in addition to concentration gradients influence the transport of Li isotopes across the blood-brain barrier. These studies demonstrate the acute pharmacokinetics of the two Li isotopes are not the same in compartmental distribution and rate of disappearance from plasma. It is conceivable 6Li may have a greater toxic or therapeutic effect than 7Li in the treatment of manic-depressive illness.

Administration, Oral↗
PubMed1981

Platelet MAO during the alcohol withdrawal syndrome.

The authors explored platelet MAO activity in alcoholism and focused on the impact of the alcohol withdrawal syndrome on MAO values. They found that platelet MAO activity is relatively increased in alcoholic patients who are experiencing withdrawal symptoms from alcohol and that it does not appear to be stable during the period of withdrawal.

Adult↗
PubMed1980

Reuptake of biogenic amines by brain slices: effect of hydrocortisone.

Biogenic amines and steroid hormones are postulated to play an important role in human and animal behavior. Steroids may exert some control over amine activity by influencing one or more aspects of amine metabolism. The brain slice technique offers a useful in vitro system for determining biogenic amine reuptake, a major control mechanism for regulating the amount of physiologically available amine. Using this technique the effect of hydrocortisone (HC) upon the reuptake of norepinephrine (NE), serotonin (5-HT) and dopamine (DA) was studied. HC had no detectable effect upon the reuptake of NE, 5-HT, or DA by hypothalamic tissue slices.

Animals↗
PubMed1980

Lithium distribution ratios in psychiatrically normal subjects.

Lithium was administered as the carbonate to 6 psychiatrically normal subjects for 11 days. The distribution of lithium between the erythrocytes and plasma, and the effect of exogenous lithium on intracellular and extracellular electrolytes was studied. The ratio of the concentrations of lithium in the erythrocytes and plasma was apparently lower in the normal group than in the patients diagnosed to have affective disorders.

Adult↗
PubMed1979

Dissimilar effects of lithium isotopes on motility in rats.

Male Wistar rats were injected twice daily with chlorides of pure lithium isotopes, either Li-6 or Li-7. While both salts decreased mobility, the salt of Li-6 initially produced a more profound effect than the salt of Li-7. This differential effect of the isotopes proved to be time dependent and was most evident on the third day of treatment. Li-6 is likely to become a valuable tool in basic psychopharmacological research. It may possess therapeutic and/or toxic properties that are different from those of lithium salts currently used in treatment of mania.

Animals↗