Presence and distribution of urocortin and corticotrophin-releasing hormone receptors in the bovine thyroid gland.
Urocortin (UCN), a 40 amino acid peptide, is a corticotrophin-releasing hormone (CRH)-related peptide. The biological actions of CRH family peptides are mediated via two types of G-protein-coupled receptors, CRH type 1 (CRHR1) and CRH type 2 (CRHR2). The aim of this study was to investigate the expression of UCN, CRHR1 and CRHR2 by immunoprecipitation, Western blot, immunohistochemistry and RT-PCR in the bovine thyroid gland. Immunoprecipitation and Western blot analysis showed that tissue extracts reacted with the anti-UCN, anti-CRHR1 and anti-CRHR2 antibodies. RT-PCR experiments demonstrated that mRNAs of UCN, CRHR1 and CRHR2 were expressed. UCN immunoreactivity (IR) and CRHR2-IR were found in the thyroid follicular and parafollicular cells and CRHR1-IR in the smooth muscle of the blood vessels. These results suggest that a regulatory system exists in the bovine thyroid gland based on UCN, CRHR1 and CRHR2 and that UCN plays a role in the regulation of thyroid physiological functions through an autocrine/paracrine mechanism.
Dipartimento di Medicina Veterinaria e Produzioni animali, Università di Napoli "Federico II", Via Federico Delpino, 1-80137, Napoli, Italia.
C
C
Squillacioti
A
A
De Luca
S
S
Alì
R
R
Ciarcia
G
G
Germano
A
A
Vittoria
N
N
Mirabella
D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D002417:Cattle / Q000502:physiology*; D047468:Immunoprecipitation / Q000662:veterinary; D018019:Receptors, Corticotropin-Releasing Hormone / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary; D013961:Thyroid Gland / Q000378:metabolism*; D054832:Urocortins / Q000235:genetics / Q000378:metabolism*; D000099052:CRF Receptor, Type 1
C101531:CRF receptor type 2; D018019:Receptors, Corticotropin-Releasing Hormone; D054832:Urocortins; D000099052:CRF Receptor, Type 1