A two-site immunoradiometric assay for the highly specific direct quantitation of nonacetylated beta h-EP in crude brain tissue samples has been developed with a detection limit of 10 fmol per well. The assay used two different antibodies with distinct specificities: a polyclonal rabbit anti-beta h-EP antibody binding between the middle portion and the C-terminal end of beta h-EP was bound to nitrocellulose membrane discs, a solid phase with a high protein binding capacity. In the following two incubation steps, the beta h-EP containing crude tissue extract--or the beta h-EP-standard--and, subsequently, the 125I-labeled monoclonal 3-E7 mouse antibody directed against the N-terminus of beta h-EP were added. Binding of beta h-EP to the solid phase antibody in the first incubation step was not affected by the addition of cross reacting opioid peptides derived from beta h-LPH up to 10 pmol per disc. Nonspecific binding of the labeled antibody to the solid phase could be lowered to 3% of total counts by the use of PBS containing nonfat dry milk as blocking solution and incubation buffer, a procedure that did not reduce maximum specific binding. Dilution studies performed with extracts sampled from the anterior hypothalamus excluded the interference of tissue factors in the assay.

Brain↗

PubMedDate not supplied

Doxepin and ethanol interaction.

The effect of short-term oral administration of doxepin, a tricyclic antidepressant, on voluntary drinking of ethanol was studied in the rat as a function of sex. The effects of doxepin on ethanol and acetaldehyde metabolizing enzymes of hepatic and selected endocrine tissues were made in the presence and in the absence of ethanol. A reduction in voluntary ethanol intake was determined after the initial doxepin dose. This effect was not apparent during continued drug administration. Subsequently, a statistically insignificant reduction of ethanol drinking was noted 24 h and 72 h post-drug termination. Hepatic alcohol and aldehyde dehydrogenase were not altered from respective controls by doxepin in the presence and absence of ethanol. Epididymal and testicular adlehyde dehydrogenase were inhibited by doxepin from control in rats maintained on ethanol or water, respectively. The results suggest lack of adverse effect of doxepin on peripheral metabolism of alcohol metabolizing enzymes as compared to adverse interaction with acetaldehyde metabolizing enzyme in the endocrine tissues studied.

Acetaldehyde↗

PubMedDate not supplied

Hierarchy of baby-linked immunogenetic risk factors in the vertical transmission of hepatitis C virus.

Mother-to-infant transmission of Hepatitis C Virus (HCV) represents the major cause of pediatric HCV infection today. Immunogenetic influence has been poorly investigated and mainly confined to HLA-class II serological polymorphisms. Among 290 parities, 135 from Pavia and 155 from Bergamo, of HCV-RNA-infected Italian women, 21 babies (7.24%) were HCV-RNA positive at birth and steadily positive over 20 months of life. All the 21 infected babies and 44 randomly selected uninfected ones, born to HCV-RNA+ mothers but steadily negative for HCV-RNA during a follow-up of 2 years, and their mothers were investigated for HLA-G, -C, -DRB1, -DQA1 and -DQB1 genomic polymorphisms. Among the different covariates, HLA-Cw*07, -G*010401, -DRB1*0701, -DRB1*1401 and homozygosity for HLA-G 14bp deletion can be considered as risk factors for HCV vertical transmission. On the contrary, protection was conferred by the HLA-DQB1*06, -G*0105N, -Cw*0602, DRB1*1104 and -DRB1*1302 alleles. Our initial question was: has the immunogenetic profile any role in the protection of the fetus growing in an infected milieu and, if so, is it independent from the other non-immunogenetic parameters? The answer to both questions should be yes.

Adult↗

PubMedDate not supplied

The use of reverse-phase chromatographic procedures coupled with radioimmunoassay in studying regional distribution of beta h-endorphin in the human brain.

Fast reverse-phase chromatographic procedures (Sep-Pak C18 cartridges and high pressure liquid chromatography) combined with radioimmunoassay is presented. It provides accurate assessment of brain tissue concentrations of beta h-endorphin (beta h-E). The method was used to study the distribution of the endogenous opioid in nine distinct human brain regions. The beta h-E was found mainly localized in the hypothalamus anterior, hypothalamus posterior followed by a lower concentration in the Corpora mamillaria and the Substantia grisea centralis. Concentrations below 1.0 fmol/mg fresh brain tissue were determined in the Pons dorsalis, Substantia nigra, Colliculi inferiores, Glandula pinealis and in Nucleus ruber.

Brain Chemistry↗