Distribution and partial characterisation of immunoreactivity to the putative C-terminus of rat pancreastatin.
The presumptive C-terminal nonapeptide of rat pancreastatin was synthesised based upon the sequence of rat chromogranin A (CGA) analogous to that of porcine pancreastatin as contained within porcine CGA. Antisera were produced which were used to determine the qualitative and quantitative distribution of pancreastatin-like immunoreactivity in rat tissues by immunocytochemistry and radioimmunoassay respectively. Pancreastatin-like immunoreactivity was most abundant in pituitary, adrenal, gastric corpus and thyroid with considerably lower levels detected in the remainder of the gastroentero-pancreatic system and brain. Immunoreactivity was localised exclusively in endocrine cells and the relative abundance of immunoreactive cells paralleled the levels obtained radioimmunometrically. Chromatographic characterisation of pancreastatin-like immunoreactivity revealed molecular heterogeneity. Immunoreactive peptides of similar size to synthetic rat pancreastatin were present in gastrointestinal tissues and thyroid. These data indicate a tissue specific processing of CGA in the rat.
Curry
W J
WJ
Department of Medicine, Queen's University, Belfast, N. Ireland.
Johnston
C F
CF
Shaw
C
C
Buchanan
K D
KD
D000818:Animals; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D053379:Chromogranin A; D002864:Chromogranins / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D010187:Pancreatic Hormones / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014018:Tissue Distribution
D053379:Chromogranin A; D002864:Chromogranins; D010187:Pancreatic Hormones; D010446:Peptide Fragments; C050836:pancreastatin