Heterogeneity of immunoreactive dynorphin B-like material in human, rat, rabbit and guinea-pig heart.
Immunoreactive dynorphin B-like material (ir-dyn B) was detected in acetic acid extracts of human atrial specimens and of rat, rabbit and guinea-pig atria and ventricles by a validated radioimmunoassay. Levels were high in rabbit atrium (66.76 +/- 7.04 pmol/g) but lower and superimposable in human and rat atria (28.18 +/- 3.20 and 30.22 +/- 2.45 pmol/g, respectively). Gel permeation chromatography revealed ir-dyn B eluting close to column exclusion and in forms with an apparently higher molecular weight than authentic dyn B in human and rat samples. In contrast, almost all the immunoreactivity from rabbit and guinea-pig acetic extracts eluted as a single peak in the region of standard dyn B. Reverse-phase high performance liquid chromatography of the pooled gel chromatography fractions of this peak showed up a molecular form with the same retention time as authentic dyn B and a second minor peak of unknown immunoreactive material eluting three fractions earlier. Digestion with carboxypeptidase B excluded the hypothesis that this latter could be dyn B-Arg14. Therefore, it might be a metabolite of endogenous dyn B recognized by the antibody used in this study.
Spampinato
S
S
Institute of Pharmacology, University of Bologna, Italy.
Canossa
M
M
Ventura
C
C
Bachetti
T
T
Venturini
R
R
Bastagli
L
L
Bernardi
P
P
Ferri
S
S
D000818:Animals; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004399:Dynorphins / Q000032:analysis*; D006168:Guinea Pigs; D006325:Heart Atria / Q000737:chemistry; D006352:Heart Ventricles / Q000737:chemistry; D006801:Humans; D007031:Hypothalamus / Q000737:chemistry; D008297:Male; D009206:Myocardium / Q000737:chemistry*; D011817:Rabbits; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013045:Species Specificity
D004399:Dynorphins