Eskil Hansson

DISTRIBUTION OF NICOTINE IN THE CENTRAL NERVOUS SYSTEM

In earlier studies from this laboratory (Hansson & Schmiterlow, 1962; Appelgren et al., 1962; Schmiterlow & Hansson, 1965), we have shown that the CNS rapidly accumulates nicotine after various routes of administration. We also found that nicotine and/or its metabolites leave the CNS fairly rapidly, a finding which explains the contradictory results reported by various earlier authors (for review, see Larson et al . , 1961). The present paper is a review of some of our earlier experiments and contains new data on the distribution and metabolism of 14Cand 3H-labeled nicotine in the brain of experimental animals.

Distribution and fate of C14-amitriptyline in mice and rats

SummaryThe physiological distribution of intramuscularly and intravenously injected C14-amitriptyline was studied in mice using an autoradiographic technique. The compound rapidly leaves the blood and concentrates in the brain, lung and heart. High concentrations are also seen in the gastric mucosa, intestines, salivary glands and lachrymal glands.The compound is rapidly metabolized in the body. The excretion studies indicate that amitriptyline is excreted to a large extent into the bile as a glucuronide conjugate.The significance of the tissue distribution in relation to the main pharmacological action and to some of the side effects are discussed.

Distribution of C14-DDT and C14-dieldrin in pregnant mice determined by whole-body autoradiography

Abstract C 14 -Labeled DDT and dieldrin were given to pregnant mice. The animals were sacrificed at various times after administration of the compounds, and the distribution of the isotope in the body was studied by means of whole-body autoradiography. The highest concentration was found in the fat tissues, liver, intestines, and mammary glands. A moderate concentration was also seen in ovaries and brain. DDT and dieldrin passed the placental barrier. A moderate activity was seen in the fetal liver and fat.

Distribution of C14-labelled amitriptyline in the cat brain

SummaryThe disposition of intravenously injected C14-amitriptyline in the brain was studied in cats. The regional distribution of the radioactivity was uneven. The concentration in the cerebral and cerebellar cortex and hippocampus, and some subcortical nuclei showed the highest accumulation a short time after the injection. Four hours after the injection the radioactivity in the grey matter decreased, when the white matter showed the highest activity. The distribution of amitriptyline was compared with C14-glucose and I131-albumin. The distribution of amitriptyline is more similar to the distribution of radioactivity after administration of C14-glucose than that after injection of I131-albumin. The implications of these distribution studies for the mode of action are discussed.