9007-12-9 Usage
Uses
Used in Bone Disorders:
Calcitonin is used as a therapeutic agent for the treatment of postmenopausal osteoporosis, hypercalcemia of malignancy, and Paget's disease of the bone. It inhibits calcium resorption from bone, causing hypocalemia, and negates the osteolytic effects of parathyroid hormone.
Used in Hypercalcemia:
Calcitonin is used as a treatment for hypercalcemia, a condition characterized by abnormally high levels of calcium in the blood. It helps to lower calcium levels by inhibiting calcium resorption from bone and increasing calcium excretion in the urine.
Used in Salmon Calcitonin:
Salmon calcitonin is the preferred source of calcitonin due to its greater receptor affinity and longer half-life than the human hormone. It is used as a more effective and longer-lasting treatment option for various bone disorders and hypercalcemia conditions.
Used in Agonists and Antagonists:
Calcitonin and its related peptide hormones, such as CGRP and AMY, have agonist activity, while salmon CT8–32 and AC512 have antagonist activity. These agents can be used to modulate the effects of calcitonin in various therapeutic applications.
Gene structure and mRNA
The human CT gene, located on chromosome 11p15.2-
p15.1, consists of six exons and five introns. CT mRNA is
coencoded with calcitonin gene-related peptide (CGRP)
mRNA in the single gene. In mammals, the synthesis
of the mRNAs encoding these two hormones is controlled
by tissue-specific alternative splicing. The CT precursor
mRNA is synthesized in thyroidal C-cells, whereas the
CGRP precursor mRNA is synthesized in neural tissues. The pufferfish ct gene consists of four coding exons. The splicing of exons 1, 2, and 3 yields CT,
whereas that of exons 1, 2, and 4 yields CGRP.
Synthesis and release
CT synthesis in thyroid C-cells and its release are stimulated principally by increased blood calcium levels. In
fish as well as mammals, a calcium-sensing receptor
has been cloned. In fasted eels, plasma CT levels were
not detectable by the specific sandwich ELISA technique
(detection limit: 30 pg/mL). In eels that were fed a high
amount of calcium-consomme solution (Ca2+: 1.25M;
1mL/100 g body weight), the plasma CT concentration
increased rapidly (CT: below detection level at 0 h to
1118.2 pg/mL at 3 h) corresponding to increased plasma
calcium levels. In fish as well as mammals, the trigger for
CT secretion appears to be primarily a change in blood
calcium levels. Recently, CT was synthesized in the osteoblasts of goldfish scales. The secretion of CT was promoted by melatonin. This regulation was also
observed in the calvariae of rats.
Receptors
The calcitonin receptor (CTR) is a member of a subfamily of the seven-transmembrane domain GPCR superfamily that includes several peptide receptors. Porcine CTR
cDNA was obtained for the first time in 1991. Subsequent
cloning of the gene demonstrated that it is approximately
70 kb in length, and contains at least 14 exons, 12 of which
encode procine CTR. Different isoforms of CTR resulting
from alternative splicing of the gene have been described
in various animal species with differential tissue expression of the transcripts. The human CTR gene has been
mapped to chromosome 7q21.3. CTRs have been identified from various vertebrates. Invertebrate CTR has also
been sequenced from the protochordate, Ciona intestinalis.
Invertebrate CTs and CTR are described in another section. The value of the dissociation constant (Kd) in rats
and trout CTR was 0.25 to 3.3 nM.
Application in Particular Diseases
In Osteoporosis:
Calcitonin is released from the thyroid gland when serum calcium is elevated. Salmon calcitonin is used clinically because it is more potent and longer lasting than the mammalian form. Calcitonin is reserved as a third-line agent because efficacy is less robust than with the other antiresorptive therapies.
Calcitonin is indicated for osteoporosis treatment for women at least 5 years past menopause. Although limited data suggest beneficial effects in men and concomitantly with glucocorticoids, these indications are not FDA approved.
Only vertebral fractures have been documented to decrease with intranasal calcitonin therapy. Calcitonin does not consistently affect hip BMD and does not decrease hip fracture risk.
Calcitonin may provide pain relief to some patients with acute vertebral fractures. If used, it should be prescribed for short-term treatment (4 weeks) and should not be used in place of other more effective and less expensive analgesics, nor should it preclude the use of more appropriate osteoporosis therapy.
The intranasal dose is 200 units daily, alternating nares every other day. Subcutaneous administration of 100 units daily is available but rarely used because of adverse effects and cost.
Originator
Calcitar,Yamanouchi,Japan,1978
Indications
Calcitonin (Miacalcin, Miacalcin Nasal Spray) is a synthetic
32–amino acid polypeptide that is identical to
salmon calcitonin. Salmon calcitonin is more potent
than human calcitonin because of its higher affinity for
the human calcitonin receptor and its slower metabolic
clearance. Administration is by subcutaneous or intramuscular
injection or by nasal spray. The absorption of
the nasal form is slower than that of the parenteral
routes.
Indications
Calcitonin release is normally stimulated by rising
serum calcium levels and suppressed by hypocalcemia.
The major physiological effects of calcitonin are inhibition
of bone resorption and deposition of postabsorptive
calcium into bone following a meal, which prevents
postprandial hypercalcemia.
Manufacturing Process
The process for the manufacture of human calcitonin in pure form from C-cell
rich medulla carcinoma of the thyroid gland or from C-cell metastasis material
is one wherein medullar carcinoma of the thyroid gland or C-cell metastasis
material, which has been defatted, for example with acetone or ether, and
which may have been first purified with alcohol or with aqueous trichloroacetic
acid, is extracted one or more times with a solvent system containing water
and an alkanol having at most 5 carbon atoms, at a pH of from about 1 to 6,
and the extracted product subjected to gel chromatography using aqueous
formic acid as eluant. The calcitonin may be separated into its constituents by
countercurrent distribution, for example by Craig distribution using a solvent
system advantageously containing n-butanol and acetic acid.
Biosynthesis
The regulation of calcitonin synthesis and release from
the parafollicular C cells of the thyroid gland is calcium
dependent. Rising serum calcium is the principal
stimulus responsible for calcitonin synthesis and release.
Other hormones, such as glucagon, gastrin, and
serotonin, also stimulate calcitonin release. Calcitonin
has been isolated in tissues other than the parafollicular
C cells (parathyroid, pancreas, thymus, adrenal),
but it is not known whether this material is biologically
active.
Secretagogues, such as gastrin and pancreozymin,
may contribute significantly to the regulation of endogenous
calcitonin. In fact, it has been postulated that
gastrin-induced calcitonin release following meals may
help regulate the postprandial calcium deposition in
bone.
A calcitonin precursor has been identified within the
thyroid parafollicular C cells. It is thought to function in
a manner analogous to that of proPTH to facilitate intracellular
transport and secretion of the hormone. The
metabolic degradation of calcitonin appears to occur in
both the liver and kidney.
Although blood calcitonin levels are normally low,
excessive levels have been found in association with
medullary carcinoma of the thyroid and more rarely
carcinoid tumors of the bronchus and stomach. Serum
calcitonin levels are used to screen and monitor patients
who have or are suspected of having medullary carcinoma
of the thyroid.
Biological Functions
In addition to its antiresorptive action via suppression of osteoclast activity, calcitonin-salmon exhibits a potent
analgesic effect and has provided considerable relief to those patients suffering from the pain associated with
Paget's disease and osteoporosis. This analgesic effect is a result of calcitonin-stimulated endogenous opioid
release. The potency of this analgesic effect has been demonstrated to be 30- to 50-fold that of morphine in
selected patients. Calcitonin is preferred over estrogen and the bisphosphonates when treatment of both
osteoporosis and related bone pain is warranted.
Acquired resistance
Resistance to calcitonin-salmon can result from the development of neutralizing antibodies.
Mechanism of action
Calcitonin interacts with specific plasma membrane receptors
within target organs to initiate biological effects.
This interaction has been directly linked to the
generation of cAMP via adenylyl cyclase activation.
Pharmacokinetics
Calcitonin-salmon differs structurally from human calcitonin at 16 of 32
amino acids. The
pharmacological activity of these calcitonins is the same, but calcitonin-salmon is approximately 50-fold more
potent on a weight basis than human calcitonin with a longer duration of action. The duration of action for
calcitonin salmon is 8 to 24 hours following intramuscular (IM) or subcutaneous (SC) administration and 0.5 to
12.0 hours following IV administration. The parenteral dose required for the treatment of osteoporosis is 100
IU/day. Initially only available by IM or SC injection, the peptide hormone calcitonin-salmon is available as
a nasal spray (Miacalcin) and as a rectal suppository. A recombinant DNA form of calcitonin salmon was
approved by the U.S. FDA in 2005 and is available as a nasal spray. The bioavailability of calcitonin-salmon
nasal spray shows great variability (range, 0.3–30.6% of an IM dose). It is absorbed rapidly from the nasal
mucosa, with peak plasma concentrations appearing 30 to 40 minutes after nasal administration, compared with
16 to 25 minutes following parental dosing. Calcitonin-salmon is readily metabolized in the kidney, with an
elimination half-life calculated at 43 minutes. As a result, the intranasal dose required is 200 IU/day. Once
the Miacalcin nasal pump has been activated, the bottle may be kept at room temperature until the medication
is finished (2 weeks)
Clinical Use
Calcitonin therapy requires the concomitant oral administration of elemental calcium (500 mg/day). Clinical
studies have shown that the combination of intranasal calcitonin salmon (200 IU/day), oral calcium
supplementation (>1,000 mg/day of elemental calcium), and vitamin D (400 IU/day) has decreased the rate of
new fractures by more than 75% and has improved vertebral BMD by as much as 3% annually. Calcitonin
prevents the abnormal bone turnover characteristic of Paget's disease of the bone and has antiresorptive
activity. In the presence of calcitonin, the osteoclast brush borders disappear, and the osteoclasts move away
from the bone surface undergoing remodeling. Side effects are significantly more pronounced when
calcitonin-salmon is administered by injection and can include nausea, vomiting, anorexia, and flushing.
Because calcitonin-salmon is protein in nature, the possibility of a systemic allergic reaction should be
considered,and appropriate measures for treatment of hypersensitivity reaction should be readily available. Although
calcitonin-salmon does not cross the placenta, it may pass into breast milk. Calcitonin-salmon is a possible
alternative to ERT; however, only limited evidence suggests that it has efficacy in women who already have
fractures.
Check Digit Verification of cas no
The CAS Registry Mumber 9007-12-9 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 9,0,0 and 7 respectively; the second part has 2 digits, 1 and 2 respectively.
Calculate Digit Verification of CAS Registry Number 9007-12:
(6*9)+(5*0)+(4*0)+(3*7)+(2*1)+(1*2)=79
79 % 10 = 9
So 9007-12-9 is a valid CAS Registry Number.
