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H Hoellinger

Publications and source records attributed to H Hoellinger.

28 records · Page 2Linked to original sources

The kinetics of cannabinoid distribution and storage with special reference to the brain and testis.

Male and female rats were given either single or repeated intramuscular injections of 2 microCi of 14C-delta 8-tetrahydrocannabinol. They were sacrificed by groups of three at regular intervals 2, 3, 4, 6, or 24 hours after the last injection. Samples of blood lung, brain and pituitary, spleen, liver, fat, testis, and ovary were removed. Some samples were pyrolysed in an automatic oxygen train system to measure 14C-CO2, which reflects total cannabinoid concentration; other samples were kept for measurements of individual cannabinoids after extraction. After a single administration of 14C-delta 8-THC, maximal concentration of total radioactivity was reached in the brain between 2 and 4 hours amounting to 6 ng/gm tissue, or 0.06 per cent of the administered dose. After two weeks of chronic administration, concentrations of radioactivity progressively increased in liver and neutral fat, while cannabinoid levels in brain and testis remained unchanged. These data illustrate the efficiency of the blood-brain and blood-testicular barrier in limiting the access and accumulation of cannabinoids in these tissues.

Animals↗

In vivo covalent binding of cismethrin and bioresmethrin to hepatic proteins.

The covalent binding level of [14C]alcohol-labelled cismethrin, bioresmethrin and/or their metabolites to hepatic proteins was measured after a single i.v. injection of pyrethroids in rats pretreated with malathion. In the first control group, the radiolabel binding level was different for cismethrin (35.3 pmol X mg-1 protein) and bioresmethrin (22.6 pmol X mg-1 protein) and in the treated rats, the amount of binding was reduced similarly for the two pyrethroids (13 pmol X mg-1 protein). After 13 days of chronic i.p. treatment, the covalent binding level on microsomal protein was 3 times higher for cismethrin than for bioresmethrin and the ratio of cismethrin to bioresmethrin covalent binding level was similar to that after a single i.v. injection. It is suggested that the difference in covalent binding distribution and concentration in the various subcellular fractions of liver was due to the different routes of metabolism of the two resmethrin isomers.

Animals↗

Effects on rats of subacute intoxication with deltamethrin via an osmotic pump.

To explore the possibility of liver enzyme induction by deltamethrin, subacute intoxication was carried out in rats for 28 days, by administration 7.2 mg.Kg-1.day-1 of deltamethrin i.p. delivered by an osmotic pump inserted in the peritoneal cavity. The body weight curve of the treated rats increased slightly but not significantly compared to the controls. No neurotoxic effect was observed. Blood parameters were unchanged, except for eosinophilia and an increase in the plasma Na+ level. Cytochrome P-450, cytochrome b5, NADPH-cytochrome c reductase, esterases and the activities of six mixed function oxidases were assayed. No variation was noted. Ultrastructural study of the liver, more specially in midlobular region, showed that deltamethrin increased the number of mitochondria and altered their shape which became irregular. These findings were consistent with morphometric results. Succinate cytochrome c reductase, citrate synthase and cytochrome c oxidase were essayed, only this last showed a significant enhancement in deltamethrin treated rats.

Animals↗

[Binding of delta-8-THC to human serum proteins: binding as a function of lipoprotein composition].

In accordance with the function of the human lipoprotein composition, using serum of different lipid profiles, the distribution of delta8tetrahydrocannabinol, as isomer of delta9THC, was studied through the use of ultracentrifugation and fraction isolation, followed by biochemical analysis of the VLDL, LDL, and HDL fractions, as well as that of the non-lipoprotein protein fraction. The results indicate the existence of a linear correlation between the distribution of delta8THC and the phospholipids of the lipoprotein cenapse. No correlation between the quantity of bound delta8THC and the other lipoprotein constituents cholesterol, triglycerides, total lipids or protein could be observed.

Blood Proteins↗