Distribution of immunoreactive growth hormone-releasing hormone in the human brain and intestine and its production by tumors.
A recently developed RIA for human pancreatic tumor GH-releasing hormone (hpGRH1-44NH2) was used to investigate its distribution in the human gastrointestinal tract and brain, and to determine the incidence of its production by tumors. GRH-immunoreactivity (GRH-IR) was present in several regions of the human brain, the highest concentration occurring in the hypothalamus, septum, and substantia inominata. In the gastrointestinal tract GRH-IR was present in the upper intestine, where it was confined to the epithelial mucosa. Approximately one third of all tumors examined (35 out of 97) contained significant amounts of GRH-IR. Gel chromatography of brain and intestinal extracts, and of several tumors, revealed the presence of two molecular forms of GRH-IR, one coeluting with the synthetic hpGRH1-44 amide standard (and also hpGRH1-40) and another eluting significantly later. The earlier eluting GRH-IR peak was found to be similar to the synthetic hpGRH1-44 NH2 and hpGRH1-40 on high pressure liquid chromatography analysis.
D000328:Adult; D000368:Aged; D001923:Brain Chemistry; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D005260:Female; D013007:Growth Hormone-Releasing Hormone / Q000096:biosynthesis / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000378:metabolism*; D011863:Radioimmunoassay
D013007:Growth Hormone-Releasing Hormone