Pharmacology hormones and reproduction, etc Flashcards
List endocrine glands
pituitary
adrenals
thyroid
ovaries /testicles
pancreas
kidneys.
Some factors that influence the hypothalamus are
Odors
Sounds
Sights
Stress
Temperature
Photoperiod (amount of time the animal is exposed to light)
Hormonal feedback
The hypothalamus releases substances that stimulate (related to endocrine system)
the pituitary gland to release trophic (growth-type) hormones, which travel through the blood to various organs. The organs are then stimulated to release other hormones or perform other actions
Negative feedback
Where high levels of hormone decrease the activity of the hypothalamus.
Positive feedback
Low levels of the hormone cause increased activity of the hypothalamus.
neurohormonal reflex (reproduction)
Applies to the release of oxytocin caused by milking, birth, or sensory stimuli associated with milking.
Four phases of reproductive system
Proestrus
Estrus
Diestrus
Anestrus
gonadotropin releasing hormone
(GnRH).
Causes the release follicle stimulating hormone (FSH) and luteinizing hormone (LH).
control the estrous cycles in animals.
Used to treat cystic ovaries in cattle
follicle stimulating hormone
FSH
causes a follicle to form, and this follicle begins to release estrogen
Estrogen
is a hormone that causes the body to transition from proestrus to estrus.
negatively feeds back to the estrogen
increase uterine tones
treats persistent corpus luteums in cattle.
used to help expel retained placentas or to induce abortion
Examples include estradiol and diethylstilbestrol (DES)
Liver
luteinizing hormone
LH
causes the mature follicle to ovulate and begin to form a corpus luteum.
corpus luteum
Begins to release progesterone and starts the cycle into diestrus.
the corpus luteum helps maintain the pregnancy
Progesterone
Growth producing hormone
prepares the uterus for reproduction and also decreases the production of GnRH through negative feedback.
Processed by liver
Gonadotropins
drugs that act like GnRH, LH, or FSH
FSH-p
the p is for pituitary) is used for superovulation and to help breed animals outside of their natural breeding seasons.
used in embryo transfer (ET) programs
Female hormone physiology
hypothalamus releases gonadotropin releasing hormone (GnRH).
causes the pituitary gland to release follicle stimulating hormone and luteinizing hormone,
FSH causes a follicle to form, and begins to
release estrogen.
the body to transitions from proestrus to estrus.
The animal shows signs of heat.
if not fertilized LH causes the mature follicle to ovulate and
begin to form a corpus luteum (ovary).
corpus luteum begins to release progesterone and starts the cycle into diestrus.
Progesterone prepares the uterus for reproduction and also decreases the production of GnRH through negative feedback
Androgens
Male sex hormones and help promote weight gain, red blood cell formation, and tissue anabolism (or growth).
Can help prevent estrus in female dogs.
In horses, they’re sometimes used to help synchronize breeding.
Androgens are regulated as Class III controlled substances, due to their potential for abuse by people.
Processed by the liver
Progestins
have the same effects as progesterone
Prostaglandins
Used to help abort pregnancies, induce parturition (giving birth), or treat pyometra.
Processed by the liver
Bonus - don’t need to do this: Prostaglandins have “prost” as part of their name and include dinoprost tromethamine and cloprostenol sodium.
To help induce labor, aid in the delivery of the newborn, or to help clear the uterus of fluids after birth you can give_____ And it is processed by
Oxytocin
Liver and kidneys
The thyroid gland is involved with many bodily processes, including the following:
Heart rate
Body temperature
Metabolic rate
Metabolism
Skin condition
Thyroid gland hormones
convert iodine into two active hormones, T3 and T4.
T3 is the active form of the hormone, whereas T4 is the inactive form
Hypothyroid animals treatment
supplement the diet of the animal with synthetic T4, (example is levothyroxine).
T4 is much cheaper than T3 and is usually readily converted to T3 in the body.
Some animals lack the enzyme to convert T4 to T3 and will need supplementation with T3 itself, but this phenomenon isn’t common.
Hyperthyroid animals treatment
require a drug that blocks the formation of thyroid hormones.
Radioactive iodine is another treatment that involves an injection taken up into the thyroid gland.
–The radioactivity destroys the thyroid tissue
Surgical removal of a thyroid gland is possible if only one gland is affected,
–hyperthyroid cats can be poor surgical candidates if the disease is advanced.
Hypoadrenocorticism
Addison’s disease
The adrenal gland is unable to produce aldosterone and glucocorticoids needed to sustain life.
The signs are weakness, collapse, and diarrhea.
fatal if not treated.
Hypoadrenocorticism Treatment
Desoxycorticosterone pivalate (DOCP) or Fludrocortisone is given to replace the effects of the hormone aldosterone. In addition, glucocorticoids prednisone or dexamethasone are used to replace the natural glucocorticoids that missing in a dog with hypoadrenocorticism.
Hyperadrenocorticism
Cushing’s disease
oversecretion of aldosterone and glucocorticoids by the adrenal gland.
common endocrine disorder of dogs and horses.
cause is a tumor in the pituitary gland
The goal of treatment is to prevent the excess secretion of cortisol and other corticosteroids.
Ketoconazole, mitotane, trilostane and selegiline.
Selegiline sometimes is an effective treatment but it doesn’t work well in the majority of dogs.
pancreas
Produces both insulin and glucagon.
Type 1 diabetes mellitus
untreated diabetic animals cannot use carbohydrates as an energy source
Glucagon
raises blood sugar levels
Insulin
decreases blood sugar levels.
Type 1 diabetes mellitus
occurs when the body doesn’t produce enough insulin and hyperglycemia (too much sugar in the blood) occurs.
Type 1 responds to injectable insulin therapy which replaces the missing hormone,
Type 2 diabetes mellitus
occurs when the peripheral tissues become resistant to the influence of insulin.
type 2 can be treated with a strict low carbohydrate diet.
Concentrations of insulin
U-40, U-100, and U-200 are different concentrations of insulin.
U-40 has 40 units of insulin per milliliter of drug.
insulin administration (how t9)
Never shake an insulin bottle, because insulin is very fragile! Gently roll the insulin bottle between your hands to mix the contents before administration, especially if the product has settled while being stored.
An insulinoma
A tumor of the pancreas that secretes large amounts of insulin.
Only one drug, diazoxide, will raise the blood sugar levels.
Growth-promoting hormones use
Used to help
–recovery from a prolonged sickness,
–gain weight
–improve feed efficiency to maximize profits in food animals.
can be implanted in the skin of food animals to give a slow release of the product over time.
They contain combinations of estradiol, progesterone, testosterone, trenbolone, and zeranol
Anabolic steroids
can be used to help promote growth (an anabolic effect).
Regulated as controlled substances and need to be closely monitored for human abuse.
meds with “gest” in them
the progestins
hyperthyroid symptoms
fast heart rates
Lose weight despite eating
May be hyperexcitable
Hypothyroid animals
are:
Lethargic
Afflicted with poor skin and hair coat conditions
Often bradycardic
