This note will be helpful for Pharmacy Students searching for analogues and inhibitors of various hormones in human body. - anterior Pituitary hormones - hormone functions -inhibitors -similar working drugs -one day assignment size

1.  Anterior Pituitary hormones
The anterior part of Pituitary gland secrets six hormones thoseare
i. Growth Hormone(GH)
ii. Prolactin (Prl)
iii. Adrenocorticotropic Hormone(ACTH / Corticotropin)
iv. Thyroid Stimulating Hormone (TSH / Thyrotropin)
v. Follicle Stimulating Hormone (FSH)
vi. Leutenizing Hormone(LH)
*The FSH and LH works together and called by the name of Gonadotropic
Releasing Hormone(GnRH)
1. Growth hormone(GH):
 Growth hormone(GH) or somatotropic hormone(STH) is secreted by
acidophil cell of anterior pituitary gland. The secretion of GH fromthe
anterior pituitary is controlled by hypothalamus through GH releasing
factor.
 Functions of GH:
1. Increasebody growth
2. Protein metabolism
3. Fat metabolism
4. Carbohydratemetabolism
Hypersecretion of GH in the young causes “Gigantism” and in adult it causes
“acromegaly”. Hypo-secretion of GH in young causes “Dwarfism”.
 GH analogues: There are three types of GH analogues:
1. Somatropin: DNA recombinant GH
2. Somatrem: Derivativeof GH
3. Sermorelin acetate: Synthetic formof GH releasing factor

2. Use: These are used for replacement therapy in GH deficient children and for
patients with Turner’s syndrometo improveadult height.
 GH inhibitors: These are somatostatin analogues like Octeretide,
Lanreoptide and Valpreotide, these analogues decrease GH secretion. GH
antagonistlike Pegvisomanthas been developed for the treatment of
acromegaly.
2. Prolactin Hormone(Prl):
 Itis a peptide hormonesecreted by acidophilic cells of anterior pituitary. It
is responsiblefor lactation in the post-partum stateof women.
 Prolactin inhibitor:
1. Pergolide and Cabergoline: These are ergot alkaloids.
2. Bromocriptine: A semisynthetic ergot alkaloid
3. Quinagolide: It is a non-ergot
These are dopamine D2 receptor stimulant and used in the treatment of
hyperprolactinemia, galactorrhoea and purperallactation. It also induces
ovulation and permits women to become pregnant.
 Prolactin analogues:
There are no Prolactin analogues Currently in use in Medicinal Pharmacy
but whereas D2 receptor agonists suppress prolactin secretion, dopamine
D2 receptor antagonists like domperidone and metoclopramide havethe
opposite effect, powerfully inducing the pituitary secretion of prolactin, and
are sometimes used as prolactin releasers.
3. Adrenocorticotropic Hormone (ACTH):
 ACTH hormonecontrols the production of another two hormones called
Cortisol and Adrenaline. Cortisol is made by the adrenal glands justas
Adrenaline, two small glands located above the kidneys. Cortisolplays an
important role in helping to:
1. Respond to stress
2. Fight infection

3. 3. Regulate blood sugar
4. Maintain blood pressure
5. Regulate metabolism, the process of how body uses food and energy.
Talking about Adrenaline it is a quicker reacting hormonethat regulates Fight of
Flight responsein human body.
 ACTH inhibitor:
Drugs that suppress adrenocorticotropic hormone(ACTH) secretion are less
popular as standard treatment and include cyproheptadine, valproic acid,
cabergoline, somatostatin analogs, PPAR-gamma agonists, vasopressin
antagonists.
 ACTH analogues:
Synthetic derivatives of ACTH are used principally in the diagnostic
assessmentof adrenocorticalfunction. Because corticosteroids mimic the
therapeutic effects of ACTH, synthetic steroids generally areused
therapeutically instead of ACTH.
4. Thyroid Stimulating Hormone (TSH):
 TSH hormoneis a hormonesecreted fromthe Anterior Pituitary to control
the thyroid glands secretions (T4 and T3). The thyroid is a small, butterfly-
shaped gland located near throat. The thyroid makes hormones that
regulate the way human body uses energy. Italso plays an important role in
regulating body weight, body temperature, musclestrength, and even
person’s mood.
 TSH inhibitors:
A small subsetof medications including glucocorticoids, dopamineagonists,
somatostatin analogs and rexinoids affect thyroid function through
suppression of TSH in the thyrotropeor hypothalamus. Fortunately, mostof
these medications do not cause clinically evident central hypothyroidism.

4.  TSH analogues:
There is no analogue drug currently in use in the clinical pharmacy but
similar requirements can be fulfilled by the use of synthetic thyroid
hormonelevothyroxine which is normally used in treatment of
hypothyroidism.
5. Gonadotropic Releasing Hormone(GnRH):
Follicle stimulating hormone(FSH) & Luteinizing hormone(LH) both
together makes the Gonadotropic Releasing Hormone.
- FSH in female it induces follicular crow causes development of ovum
and secretion of estrogens. In makesupports spermatogenesis and has
trophic influence on seminiferous tubules.
- LH in female induces pre-ovulatory swelling of the ripe Graafian follicle
and triggers ovulation. Also responsiblefor progesteronesecretion. In
male stimulate testosterone secretion.
 Gonadotropins Inhibitor:
Danazolis a synthetic steroid analogue with strong antigonadotropic
activity (inhibits luteinizing hormone [LH] and follicle-stimulating hormone
[FSH])
 Gonadotropins analogues:
GnRH injected i.v. (100 µg) induces promptrelease of LH and FSH but
causes rapid enzymatic degradation so shorter plasma t/2 (4-8 min) Used
for testing pituitary gonadal axis in male as well as female hypogonadism.
Example of Super-active / long-acting GnRH agonists is Nafarelin, Goserelin,
Triptorelin & Leuprolide.