Substance P in tumors: pheochromocytoma and carcinoid.
Immunoreactive substance P (I-SP) was measured in two pheochromocytomas and a carcinoid of the caecum. The pheochromocytomas contained 1,5 and 50 pmol/g I-SP respectively. An HPLC analysis I-SP and catecholamines were enriched in the chromaffin granule fraction. The carcinoid contained 2900 pmol/g I-SP. About 40% of the immunoreactivity behaved like substance P on gel filtration, HPLC and in bioassays (fall in rabbit blood pressure and contraction of the guinea-pig ileum which was abolished by specific tachyphylaxis to substance P). These results indicate that authentic substance P is present in carcinoids and pheochromocytomas and that in the latter it is most likely stored in chromaffin granules.
D000310:Adrenal Gland Neoplasms / Q000378:metabolism*; D000818:Animals; D001681:Biological Assay; D001794:Blood Pressure / Q000187:drug effects; D002276:Carcinoid Tumor / Q000378:metabolism*; D002395:Catecholamines / Q000378:metabolism; D002430:Cecal Neoplasms / Q000378:metabolism; D002837:Chromaffin Granules / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D010673:Pheochromocytoma / Q000378:metabolism*; D011817:Rabbits; D051381:Rats; D013004:Somatostatin / Q000378:metabolism; D013373:Substance P / Q000378:metabolism* / Q000494:pharmacology
D002395:Catecholamines; D013373:Substance P; D013004:Somatostatin