Health Newsletter - #2
Commercial preparations of hCG contain Beta-endorphin.
These results suggest that placental extracts (especially chorionic gonadotropin preparation) may contain immunoreactive β-endorphin as well. We tried to determine immunoreactive β-endorphin content in a chorionic gonadotropin preparation (Pregnyl). The content of immunoreactive β-endorphin in the chorionic gonadotropin preparation was demonstrated as > 266 pg/5,000 IU of chorionic gonadotropin per ampule. However, the dilution curve of the chorionic gonadotropin preparation did not show a parallelism with the standard curve of β-endorphin. Odagiri et al2 also observed nonparallelism in the dilution curves of the placental extracts-1M acetic acid, glacial acetic acid, glacial acetic acid/acetone, and Payne's extraction procedures,3 although parallelism was found with water extract of placenta.
Production of choriogonadotropin-like factor by a microorganism.
Extracts from an acetone powder preparation of a culture of a microorganism tentatively named Progenitor cryptocides contain choriogonadotropin (CG)-like factor as determined by radioimmunoassay with antiserum to human (h)CG beta subunit COOH-terminal peptide and radioreceptor assay with bovine corpus luteum membranes. The biological activity of the purified factor as determined by the rat uterine weight assay and the ovarian weight assay was equivalent to 380 (95% confidence limits: 320-490) and 880 (780-1020) international units/mg, respectively. It can be concluded from the present results that a microorganism produces a glycoprotein that is biologically active and has physicochemical properties similar to those of hCG.
Human chorionic gonadotropin-like substance in nonendocrine tissues of normal subjects.
By means of two assay systems, a beta chain human chorionic gonadotropin radioimmunoassay and a radioreceptor gonadotropin assay, a chorionic gonadotropin-like substance was demonstrated in extracts of liver and colon obtained at autopsy from three patients who died of nonneoplastic disease. In contrast to placental chorionic gonadotropin, colon and liver chorionic gonadotropin was not bound to concanavalin A-Sepharose columns, indicating that this substance possessed little or no carbohydrate. Previous workers demonstrated that desialylated human chorionic gonadotropin possesses little or no bioactivity in vivo but retains full radioreceptor and radioimmunoassay activity in vitro. Since many normal tissues produce chorionic gonadotropin, bioactivity may be modulated by regulation of carbohydrate content.
Neuroanatomical correlates of hunger and satiation in humans using positron emission tomography.
The central role of the hypothalamus in the origination and/or processing of feeding-related stimuli may be modulated by the activity of other functional areas of the brain including the insular cortex (involved in enteroceptive monitoring) and the prefrontal cortex (involved in the inhibition of inappropriate response tendencies) In this study, positron emission tomography (PET) measurements of regional cerebral blood flow (rCBF), a marker of neuronal activity, were used to investigate the regions of the human brain that are preferentially affected during hunger and satiation. We tested the hypotheses that the hypothalamus, insular cortex, and prefrontal cortex are preferentially involved, and we explored the possibility that additional brain regions play a role in these appetitive states.
Human chorionic gonodotropin-like material: presence in normal human tissues.
With the use of radioreceptor assay for gonadotropin and a beta-chain radioimmunoassay for human chorionic gonadotropin (hCG), we have been able to demonstrate the presence of hCG-like material in all normal human tissues tested. Accordingly, we hypothesize: (1) that this hCG-like material in normal tissues has the protein structure of hCG but does not possess the carbohydrate moieties of placental hCG and probably has little or no bioactivity in vivo and (2) that the trophoblastic cell is not unique in its ability to synthesize hCG but has developed the ability to glycosylate hCG, transforming a ubiquitous cellular protein into a hormone, hCG might better be called human cellular gonadotropin.