title: Increase in calcitonin mRNA levels in rats at high risk of C cell tumours is genetically determined.
abstract: C-cells tumours are frequent (50%) in old WAG/Rij rats. In comparison to the original Wistar strain, three month old WAG/Rij rats are characterized by higher calcitonin synthesis and secretion, in addition to a genetically transmitted loss of calcitonin binding sites in the outer renal medulla. In order to determine if the increase of calcitonin gene expression is also of genetic origin, we quantified calcitonin and its specific messenger in the thyroid glands of second generation (Wistar x WAG/Rij) hybrids. These parameters ranged from low Wistar like to higher WAG/Rij like values. The amount of calcitonin messenger in the thyroid was highly correlated to the release of the hormone in plasma elicited by a calcium challenge and inversely correlated with the number of its binding sites in the kidney. Our results suggest that an enhanced expression of the calcitonin gene is genetically transmitted, probably as a consequence of the mutation involved in the loss of renal calcitonin binding sites. It may represent the first event leading to malignancy.
authors.affiliation: U 113 INSERM, CHU Saint Antoine, Paris, France.
authors.forename: M C
authors.initials: MC
authors.lastname: Delehaye
authors.forename: Z
authors.initials: Z
authors.lastname: Bouizar
authors.forename: S
authors.initials: S
authors.lastname: Minvielle
authors.forename: E
authors.initials: E
authors.lastname: Pidoux
authors.forename: N
authors.initials: N
authors.lastname: Segond
authors.forename: F
authors.initials: F
authors.lastname: Treilhou-Lahille
authors.forename: G
authors.initials: G
authors.lastname: Milhaud
authors.forename: M S
authors.initials: MS
authors.lastname: Moukhtar
mesh_terms: D000818:Animals; D001345:Autoradiography; D015152:Blotting, Northern; D002116:Calcitonin / Q000235:genetics* / Q000378:metabolism; D002277:Carcinoma / Q000235:genetics* / Q000378:metabolism; D004198:Disease Susceptibility; D005260:Female; D008297:Male; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000032:analysis*; D011863:Radioimmunoassay; D051381:Rats; D012307:Risk Factors; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D002116:Calcitonin