Helodermin-like peptides in thyroid C cells: stimulation of thyroid hormone secretion and suppression of calcium incorporation into bone.
Helodermin is a vasoactive intestinal peptide-like peptide in the salivary gland venom of the lizard Heloderma suspectum. Helodermin-like immunofluorescence was observed in the parafollicular (C) cells in several mammals and in the C cell homologues of the chicken ultimobranchial gland. Thus, helodermin-like peptides coexist with calcitonin. The results of radioimmunoassay agreed with the immunocytochemical findings. HPLC of rat thyroid extracts revealed one major peak of helodermin-like immunoreactivity, which eluted in a position close to that of lizard helodermin. Helodermin stimulated basal thyroid hormone secretion and colloid droplet formation in conscious mice. The effect of large doses of helodermin was quite long-lasting and the maximal response occurred after 2-6 hr. In addition, helodermin suppressed the incorporation of calcium into bone in conscious rats. The findings suggest that helodermin-like peptides in C cells may be involved in the local regulation of thyroid hormone secretion and in the maintenance of calcium homeostasis.
Grunditz
T
T
Department of Otolaryngology, Malmö General Hospital, Sweden.
Persson
P
P
Håkanson
R
R
Absood
A
A
Böttcher
G
G
Rerup
C
C
Sundler
F
F
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique; D006706:Homeostasis / Q000187:drug effects; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D009928:Organ Specificity; D010455:Peptides / Q000032:analysis / Q000302:isolation & purification* / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013045:Species Specificity; D013961:Thyroid Gland / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D013963:Thyroid Hormones / Q000378:metabolism*; D013972:Thyrotropin / Q000494:pharmacology; D013974:Thyroxine / Q000494:pharmacology; D014688:Venoms / Q000032:analysis
D036341:Intercellular Signaling Peptides and Proteins; D010455:Peptides; D013963:Thyroid Hormones; D014688:Venoms; C040442:heliodermin; D013972:Thyrotropin; D013974:Thyroxine; D002118:Calcium