Calcitonin and Postmenopausal Osteoporosis

Leggate, J.; Farish, E; Fletcher, Colin D.; McIntosh, W. B.; Hart, D. M.; Sommerville, J. M.

doi:10.1111/j.1365-2265.1984.tb00062.x

Cited by 45 publications

(12 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, a report of CT gene mutation in a young patient with osteoporosis also supports the idea that CT is important in maintaining bone mass (Alevizaki et al 1989). Although the correlation between CT plasma level and BMD remains unclear (Chesnut et al 1980;Leggate et al 1984;Prince et al 1989), we can speculate that a variation in the CT locus may be correlated to variations in the effect of CT in maintaining calcium homeostasis. For example, the CT secretory reaction to calcium infusion in osteoporotic women was reported to be lower than that in normal women (Taggart et al 1982).…”

Section: Discussionsupporting

confidence: 55%

Association of bone mineral density with a dinucleotide repeat polymorphism at the calcitonin (CT) locus

et al. 2000

View full text Add to dashboard Cite

Calcitonin (CT), a calcium-regulating hormone, lowers the calcium level in serum by inhibiting bone resorption. Because CT may play a role in the pathogenesis of osteoporosis, genetic variations in or adjacent to the CT gene may be associated with variations in bone mineral density (BMD). The present study examined the correlation between a dinucleotide (cytosine-adenine; CA) repeat polymorphism at the CT locus and BMD in 311 Japanese postmenopausal women (mean age, 64.1 years). Seven alleles were present in this population; each allele contained 10, 11, 16, 17, 18, 19, or 20 CA repeats. Thus, we designated the respective genotypes A10, A11, A16, A17, A18, A19, and A20. The A10 and A17 alleles were the predominant alleles in the population studied. Z scores (a parameter representing deviation from the age-specific weight-adjusted average BMD) were compared between individuals that possessed one or two alleles of each genotype and those that did not possess the allele. Subjects who possessed one or two A10 alleles had lower BMD Z scores than those who did not (lumbar 2-4 BMD Z score; Ϫ0.148 Ϯ 1.23 vs 0.182 Ϯ 1.54; P ϭ 0.04). No significant relationships were observed between allelic status and background data or biochemical parameters. The significant association observed between BMD and genetic variations at the CT locus implies that polymorphism at this locus may be a useful marker for the genetic study of osteoporosis.

show abstract

Section: Discussionsupporting

confidence: 55%

Association of bone mineral density with a dinucleotide repeat polymorphism at the calcitonin (CT) locus

et al. 2000

View full text Add to dashboard Cite

show abstract

“…We found that short term estrogen therapy did not increase basal or stimulated serum CT concentrations in postmenopausal women. Similarly, Lobo et al (18) and Selby et al (19) did not find any effect of a short term E 2 therapy on basal CT levels, and Leggate et al (20) found no increase in CT secretion after long term E 2 administration in peri-and postmenopausal women. However, as mentioned previously, others have found that estrogens stimulate CT secretion (4)(5)(6).…”

Section: Discussionmentioning

confidence: 93%

Effects of Estrogens and Calcium on Calcitonin Secretion in Postmenopausal Women*

Body

Struelens²,

Borkowski³

et al. 1989

The Journal of Clinical Endocrinology & Metabolism

View full text Add to dashboard Cite

The protective action of estrogens on bone mass may be mediated by an increase in calcitonin (CT) secretion. We reevaluated this hypothesis using a method for measuring CT in extracts of serum that allows sensitive specific measurement of CT monomer. We studied seven healthy postmenopausal women before and on the 7th and 28th days of each of three 4-week treatment periods: estrogen (estradiol valerate; 2 mg/day), calcium supplement (1500 mg/day), and estrogen plus calcium; the three cycles were separated by intervals of 4 weeks. Serum extractable CT (exCT) levels were measured before and after a short calcium stimulation test (2 mg Ca/kg in 5 min) to assess the C-cell secretory response on each day. Estrogen had the expected biological effects, decreasing (P less than 0.05) serum gonadotropin concentrations and fasting or 24-h urinary calcium excretion. The calcium supplement caused a significant increase in 24-h urinary calcium excretion. However, there was no increase in basal or stimulated serum exCT levels during any of the three cycles. On the contrary, basal serum exCT concentrations decreased slightly but significantly during estrogen treatment from 1.9 +/- 0.5 (+/- SE) to 1.5 +/- 0.4 ng/L on day 7 and 1.2 +/- 0.2 ng/L on day 28 (P less than 0.05). This decrease in basal exCT levels did not occur during the combined estrogen and calcium administration period, probably because the slight decrease in serum calcium induced by estrogen did not occur during combined estrogen and calcium administration. In summary, estrogens do not stimulate CT secretion; variations in serum exCT levels appear to be related to the changes in bone metabolism induced by estrogens.

show abstract

“…According to some authors, lack of endogenous steroids leads to decreased levels of circulating and stored calcitonin (Deftos et al 1981;Taggart, Chesnut, Ivey et al 1982) following an initial phase of calcitonin hypersécrétion (Pansini, Bettocchi, Bergamini et al 1984) and to a net reabsorption of bone minerals and osteoporosis (Nordin, Aaron, Speed & Crilly, 1981). Leggate, Farish, Fletcher et al (1984) and Tiegs, Body, Wahner et al (1985) have questioned these conclusions because they were not able to show changes in plasma calcitonin. Thus the whole problem must be reconsidered.…”

Section: Discussionmentioning

confidence: 94%

Ovarian steroids modulate the action of calcitonin in women

Pansini

Bergamini²,

Bellinazzi³

et al. 1988

Journal of Endocrinology

View full text Add to dashboard Cite

Slow i.v. infusion of salmon calcitonin into normal women led to a transient increase in plasma concentrations of cyclic AMP and to a decrease in plasma calcium, which was maintained for at least 2 h. These responses were significantly reduced in the same patients after hysterectomy and ovariectomy. In contrast, maintenance of the ovaries at the time of surgery, or substitutive hormonal therapy, seemed to restore the sensitivity to exogenous calcitonin, suggesting a permissive role of ovarian steroids in the effect of calcitonin. The most likely explanation for this phenomenon is that these hormones influence either the number of calcitonin receptors or the coupling of the receptors to the functional unit of bone adenylate cyclase.

show abstract

Calcitonin and Postmenopausal Osteoporosis

Cited by 45 publications

References 15 publications

Association of bone mineral density with a dinucleotide repeat polymorphism at the calcitonin (CT) locus

Association of bone mineral density with a dinucleotide repeat polymorphism at the calcitonin (CT) locus

Effects of Estrogens and Calcium on Calcitonin Secretion in Postmenopausal Women*

Ovarian steroids modulate the action of calcitonin in women

Contact Info

Product

Resources

About