Bioactive atrial natriuretic factor-like peptides in rat anterior pituitary.
The presence of biologically active atrial natriuretic factor (ANF)-like peptides was demonstrated in rat anterior pituitary. ANF-like immunoreactivity was detected in rat anterior pituitary by specific radioimmunoassay and was extracted from rat anterior pituitary homogenates by heat-activated Vycor glass beads; extracts were purified by reverse-phase high performance liquid chromatography. Two peaks containing ANF immunoreactive material were obtained. The first peak was eluted from the C18 mu Bondapak column at a position similar to the 28-amino acid carboxy terminal peptide (Ser99-Tyr126)-ANF of prohormone. The second peak had the same pattern of elution as the 126-amino acid prohormone, (Asn1-Tyr126)-ANF. The biological activity of the smaller molecular weight peptide (28 amino acid) was assessed by its inhibitory effect on 10(-8) M ACTH-stimulated aldosterone secretion in rat zona glomerulosa cell suspension. This ANF-like material also displaced I125-labelled ANF from rat glomerular receptors with a potency similar to synthetic (Arg101-Tyr126)-ANF. Immunocytochemical localization revealed a distribution of ANF-stained cells similar in pattern and location to that of gonadotrophs. These results suggest the existence of biologically active ANF-like peptides and ANF prohormone within the anterior pituitary. However, their role remains to be elucidated.
Gutkowska
J
J
Laboratory of Biochemistry of Hypertension, Clinical Research Institute of Montréal, Qué., Canada.
Cantin
M
M
D000302:Adrenal Cortex / Q000378:metabolism; D000450:Aldosterone / Q000378:metabolism; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D007150:Immunohistochemistry; D010903:Pituitary Gland, Anterior / Q000032:analysis*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains
C472610:atrial natriuretic peptide, rat; D000450:Aldosterone; D009320:Atrial Natriuretic Factor