Variable distribution, in four rat brain areas, of the three natural forms of peptide histidine isoleucinamide: PHI(1-27)NH2, PHI-Gly, and PHV (1-42).
Three parent peptides were shown to coexist in four rat brain regions: PHI(1-27)NH2 (peptide with an N-terminal histidine and a C-terminal isoleucinamide commonly called PHI), PHI-Gly (PHI(1-27)Gly) and PHV(1-42) (a 42 amino acids form with a C-terminal valine, consisting of PHI(1-27) C-terminally extended by the connecting peptide between PHI and VIP in the precursor molecule except for the terminal basic doublet preceding VIP). A differential distribution of the 3 forms was observed by means of radioimmunoassay, after chromatographic separation on Fractogel, in extracts from temporal cortex, hippocampus, striatum and hypothalamus. Total PHI-IR concentration was found to be higher in the temporal cortex and hippocampus than in the striatum and hypothalamus. PHI(1-27)NH2 was the major form, and accounted for 55% of total PHI-IR in the cortex and hippocampus, 62% in the hypothalamus and as much as 70% in the striatum. PHI-Gly represented 18% of total PHI-IR in the cortex and hippocampus, and 11% in the two other brain areas. PHV(1-42) represented 26% of total PHI-IR in all areas except in the striatum where it represented 18% only.
Cauvin
A
A
Department of Biochemistry and Nutrition, Medical School, Free University of Brussels, Belgium.
De Neef
P
P
Bastianelli
E
E
Robberecht
P
P
Christophe
J
J
D000818:Animals; D001923:Brain Chemistry; D003342:Corpus Striatum / Q000737:chemistry; D006624:Hippocampus / Q000737:chemistry; D007031:Hypothalamus / Q000737:chemistry; D008297:Male; D010446:Peptide Fragments / Q000032:analysis*; D010451:Peptide PHI / Q000031:analogs & derivatives* / Q000032:analysis*; D011498:Protein Precursors / Q000032:analysis*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013702:Temporal Lobe / Q000737:chemistry; D014018:Tissue Distribution; D014660:Vasoactive Intestinal Peptide / Q000032:analysis*
D010446:Peptide Fragments; D010451:Peptide PHI; D011498:Protein Precursors; C053900:peptide histidine valine 42; C060707:peptide PHI-(1-27)-glycine; D014660:Vasoactive Intestinal Peptide