BACKGROUND AND AIMS One proposed mechanism whereby hepatic encephalopathy (HE) leads to loss of brain function is dysregulated synthesis of neurosteroids. Mitochondrial synthesis of neurosteroids is regulated by "peripheral benzodiazepine binding sites" (PBBS). Expressed in the brain by activated glial cells, PBBS can be measured in vivo by the specific ligand [11C](R)-PK11195 and positron emis...

Polybrominated biphenyls (PBBs) cause a mixed-type (phenobarbital- plus 3-methylcholanthrene-like) induction of liver microsomal drug metabolizing enzymes in rats. However, 2,2',4,4',5,5'-hexabromobiphenyl and 2,2',3,4,4',5,5'-heptabromobiphenyl, which together comprise less than 80% of PBBs (FireMaster), were shown to be strictly phenobarbital-type inducers. Other components (unidentified) mus...

A series of N,N-dialkyl-2-phenylindol-3-ylglyoxylamides bearing the halogens iodine and bromine were synthesised and their binding affinity for the peripheral benzodiazepine binding sites (PBBS) in rat kidney mitochondrial membranes was evaluated using [(3)H]PK11195. Central benzodiazepine receptor (CBR) affinities were also evaluated in rat cortices using [(3)H]flumazenil to determine their se...

In the early 1970s, the largest industrial accident in the United States resulted in widespread contamination of the food supply in Michigan with polybrominated biphenyls (PBBs). The chemical similarity of PBBs to compounds implicated as endocrine disruptors has raised the question of whether PBBs could affect the reproductive system. In the present analysis we examine the relation between seru...

Background: Polybrominated Biphenyls (PBBs) and Polybrominated Diphenyl Ethers (PBDEs) are semi-permanent Halogenated compounds that are mainly used in flame retardant. These contaminants as endocrinedisrupting associated with dysfunction of immune, endocrine and nervous systems. Influence various physiological processes such as menarche, birth weight, fetus growth and development, head circumf...

This issue of ENVIRONMENTAL HEALTH PERSPECTIVES represents papers presented at the October 1977 conference on the Scientific Aspects of Polybrominated Biphenyls (PBB) sponsored by the Michigan State Agricultural Experiment Station at the Kellogg Center for Continuing Education, Michigan State University, East Lansing, Michigan. PBBs were originally synthesized for use as a fire retardant in the...

UNLABELLED 11C-(R)-PK11195 is a PET radiotracer for the quantification of peripheral benzodiazepine binding sites (PBBSs). The PBBS is a consistent marker of activated microglia, and 11C-(R)-PK11195 has been used to image microglial activity in the diseased brain and in neoplasia. However, the PBBS is also expressed in the brain vasculature (endothelium and smooth muscles), and no evidence, to ...

The inadvertent mixing of polybrominated biphenyls (PBBs) into animal feed in 1973 resulted in the contamination of thousands of Michigan farms. Farm animals who ingested this feed suffered various consequences including weight loss, decreased productivity, frequent infections, skin changes, and reproductive abnormalities.' This error was not initially known, and widespread contamination of hum...