What causes dwarfism in most of the cases?
Panhypopituitarism where there is undersecretion of all ant pituitary hormones
In what percentage of dwarfs is there undersecretion of growth hormone alone?
33.3% (1/3)
The dwarf still matured sexually and is able to reproduce
What’s the cause of dwarfism in the LeviLorain dwarf?
The LeviLorain dwarf is able to produce growth hormone but there is an hereditary inability to form somatomedin C(a hormone produced by the liver that promotes the action of growth hormone)
What disease is associated with over secretion of growth hormone in childhood?
Hyperglycemia due to oversecretion of GH, which antagonises the action of insulin leading to degeneration of beta cells
In 10% of giants, it leads to full blown diabetes
Inability to produce growth hormone in adult hood can lead to ……
Increased rate of aging due to decreased protein deposition in most tissues of the body and replacement with fat
What percentage of secretory cells do the gonadotrophs make up?
20%
What is the name of the secretory cells of the testes?
Leydig cells that secrete testosterone
What cells help to support sperm cell maturation?
Sertoli cells
How many amino acid residues does thyroglobulin have and what is its molecular weight?
140
660000
What’s the minimum daily intake of iodine I order to avoid diseased state of thyroid gland?
100-150mg
What percentage of iodide is used by the body?
1/3 is used by thyroid gland
2/3 is excreted
What stimulates the endocytosis of organified thyroglobulin back into the cell?
TSH
Propylthiouracil helps to prevent …….. by inhibiting ………..
Hyper thyroidism
Thyroperoxidase
Concerning transportation of thyroid hormones, state the percentage of how they are transported?
67% by tyrosine binding globulin
20% by tyrosine binding prealbumin
13% by albumin
In what form is thyroid hormone physiologically active?
In free form(same as Ca)
What are the daily amounts of thyroid hormone secreted?
80mg T4
4 mg T3
2mg rT3
What is the effect of Stress on TSH?
Decreases TSH levels
Glucocorticoids inhibit the secretion of TRH
What’s the effect of low thyroid hormones in men and women?
Low libido in men
Frequent menstrual bleeding in women and irregular periods
What’s the effect of high levels of thyroid hormones in men and women?
Impotence in men
Reduced menstrual bleeding and amenorrhea
What are the main functions of aldosterone?
Na reabsorption
K and H secretion
What steroidal hormone antagonizes vitd3
Cortisol
NE causes vasoconstriction via ….. while epinephrine causes vasodilation via ….
Alpha receptors
Beta 2 receptors
What’s the action of catecholamines on K conc?
Initial rise in K, prolonged fall in K because it’s entry into the cell is increased
Deficiency of 21 beta hydroxylase leads to what?
Undersecretion of cortisol and aldosterone with oversecretion of androgens leading to adrenogenital syndrome or congenital adrenal hyperplasia
Deficiency of 17 alpha hydroxylase leads to what symptoms?
Inability to produce androgens and cortisol but excessive amounts of aldosterone is produced
What are the physiologic effects of dopamine?
Increased renal blood flow
+ve ionotropic effect on the heart
Increased systolic bp, but doesn’t affect diastolic BP?
What are the stimulus for the release of adrenal medulla hormones?
Sym Ns
Hypoglycemia
What’s the length of the pineal gland?
10mm
What are the examples of sulfonylurea drug?
Tolbutamide, glyburide
What’s the function of metformin?
It’s a biguanide drug which up regulate insulin receptors on target tissues. It helps to treat lifestyle diabetes
What hormone is regarded as the hormone of Abundance?
Insulin
What hormone is regarded as the hormone of starvation?
Glucagon
Beta adrenergic …… levels while alpha adrenergic agents ………
Increases cAMP
Decreases cAMP
What are the stimulators factors for the release of somatostatin?
Nutrients
Glucagon
Beta adrenergic agonists
Somatostatin is inhibited by what hormone and inhibits what hormones?
Insulin
Insulin and Glucagon
What quantity of Calcium is ingested per day?
1000mg
Only about 1/3 is absorbed from GIT into ECF
About 190mg is lost back to the gut
What is chvostek sign indicate?
The Chvostek sign is a clinical finding associated with hypocalcemia, or low levels of calcium in the blood. This clinical sign refers to a twitch of the facial muscles that occurs when gently tapping an individual’s cheek, in front of the ear.
Constipation, polyuria and dipsia , lethargy and hyporeflexia are usually symptoms seen in
Hypercalcemia
Hypocalcemia is characterized by what symptoms?
Hyperreflexia
Muscle cramps
Spontaneous twitching
Tingling and numbness
Trousseau sign indicates ………
Hypocalcemia
It is indicated by carpopedal spasms
How many amino acids does PTH have?
84 aa, secreted by chief cells
Biological activity is on N terminal 34 amino acid
In what part of the kidney is calcium reabsorbed under the influence of PTH?
Distal tubule
PTH action on the kidney, what happens?
Promotes PO4 secretion at PCT and Ca reabsorption at DCT
Secondary hyperparathyroidism is usually caused by
Vit D deficiency or chronic renal failure
There are high levels of PTH in the blood, but blood levels of Ca are low or normal, but never high
What’s the treatment for hypoparathyroidism?
Ca supplements
And supplements of active vit d3
Albright’s hereditary osteodystrophy is characterized by
Pseudohypoparathyroidism (PHP) is a genetic disorder in which the body fails to respond to parathyroid hormone.
Furosemide is used to treat ……..
Hypercalcemia by inhibiting Ca reabsorption
Etidronate is used to treat ……
Hypercalcemia by inhibiting bone resorption
How many amino acids does Calcitonin have?
32
What is the effect of cortisol on ca metab?
Decreases serum ca
Antagonises Vit d3 so it prevents absorption of ca and PO4 from the gut
…. Increases renal Ca excretion and increases absorption of Ca from the gut. Net effect is +ve
Growth hormone
How many amino acids does Renin have?
340aa
What are sufonylurea drugs?
Sulphonylureas are a class of oral (tablet) medications that control blood sugar levels in patients with type 2 diabetes by stimulating the production of insulin in the pancreas and increasing the effectiveness of insulin in the body.
Angiotensin II has how many aa?
8 aa
It is an octapeptide
AG II decreases GFR by……
Constriction of efferent arterioles and constriction of mesangial cells to reduce the surface area of the glomerular capillaries
AG directly increases plasma osmolality by……
Directly increasing the reabsorption of Na at the PCT
How does AG II indirectly increase BP?
It stimulates sympathetic fibres to release NE which causes vasoconstriction via alpha receptors
What’s the half life of angiotensin II?
1-2 mins
What’s the dimension of the testes?
2.5*4cm
What are the substances produced by sertolli cells?
Inhibin
Activin
Androgen binding proteins
Mullerian inhibiting hormone
How are sex hormones transported in the blood?
- Sex hormone binding globulin or gonadal steroid binding globulin 65%
- Albumin 33%
- Cortisol binding globulin to a little extent
What’s the action of cAMP on cholesterol?
Increases its conversion to pregnenolone by activating pkA
What are the characteristics of hypogonadism in childhood in males
Tallness due to late epiphyseal plate closure
Small genitalia
High pitched voice
Narrow shoulders and small muscles
Sparse body hair
Sterility due to the absence of spermatogenesis
Pubic hair with female pattern
Sterility in males may be due to ……
Little or no testosterone to stimulate spermatogenesis
What structure secretes relaxin?
Corpus luteum
What hormone increases basal body temp in females?
Progesterone
What maintains the corpus luteum and where is it produced from?
HCG
Syncytiotrophoblast and placenta later on
When does the mammary gland along with its lobules and ducts develop?
Halfway through pregnancy
The largest duct of the mammary gland is the …..
Lactiferous duct which drain into sinuses before coming out into the areola
Around what month is oogenesis completed in fetal life?
7 month
What secretes inhibin in females?
Granulosa cells
What hormone increases uterine sensitivity to oxytocin and increases uterine excitability?
Estrogen
It also increases uterine blood flow
What hormone acts as an antagonist to estrogen by decreasing the number of estrogen receptors and decreasing uterine excitability and sensitivity?
Progesterone
….. stimulates the enlargement of the lobules and alveoli of the breast?
Progesterone
At what day does the dominant follicle emerge?
Day 6
What is responsible for ovulation?
LH surge
Apart from the LH surge, how is the follicle ruptured?
Through the action of proteolytic enzymes
Progesterone
Prostaglandins
At what day does the corpus luteum degenerate of pregnancy doesn’t occur?
Around day 24
In the follicular phase, estrogen inhibits ……. And enhances …….
FSH
LH
What hormone inhibits LH?
Progesterone
In the proliferative phase, occurs from days ………. And what hormone influences this?
5-14
Estrogen that causes endometrial thickening
In the secretory phase, occurs from days ………. And what hormones influences this?
14-28
Progesterone causes the endometrium to be secretory
Estrogen causes endometrial vascularisation
Polymenorrhea is characterized by?
A menstrual cycle that’s shorter than 21 days caused by stress and endometriosis
Dysmenorrhea is characterized by ……..
Painful menstruation and menstrual cramps
What is menometrorrhagia?
Menometrorrhagia, defined as excessive and prolonged uterine bleeding occurring at irregular and/or frequent intervals, occurs in up to 24% of women aged 40-50 years.
The syncytiotrophoblast is formed ———— after fertilization?
3-6 days
The placenta is formed when?
7-8 weeks after pregnancy
At what week is hCG maximum during pregnancy?
10-12 weeks
…… is also known as human chorionic somatomammotropin?
Human placental lactogen
What hormone produced by the placenta promotes genital tract differentiation and fetal testicular secretion?
hCG
What hormone during pregnancy acts as an insulin antagonist, decreases glucose utilization by the mother and causes Na, K and Ca retention?
Human chorionic somatomammotropin
The breast ductal system dev is stimulated by …….
Estrogen
What hormone increases maternal ventilation during pregnancy?
Progesterone
In how many weeks can hCG be detected in the urine
About 2 weeks
14 days
By how many percent does CO increase in a 20 week pregnant woman?
30-40%
In pregnancy, blood volume and respiratory volume are increased by …….. but BMR is increased by ……
20%
15%
Polymenorrhea is characterized by
A cycle shorter than 21 days due to stress and endometriosis
At what week does labor start?
At week 40
Braxton Hick’s contractions are …….
Rhythmic contractions of the myometrium
How long do the stages of labor last?
1st stage- 8-24 hours
2nd stage 20-90 mins
3rd stage 15-30 mins
The shedding of the endometrium after birthing is a discharge called
Lochia
At what stage of pregnancy is the baby given birth to
2nd stage
What two hormones contribute to the functional dev of the breast by stimulating the production of the enzymes?
Prolactin and hCG
Rhythmic method of contraception involves ————-
Avoid fertile period + or - 3 days around ovulation
In how many weeks is the pre pregnant body regained after birthing?
4-6 weeks
Cholostrum contains …… and …… that helps to provide immunity to the child
Lactoferrin which has anti bacterial action and IgA
High levels of prolactin can inhibit …… and ………
Estrogen and progesterone and this can disrupt the menstrual cycle and lead to infertily. That’s why lactation during breastfeeding when there is high levels of prolactin, can be used as a form of natural contraceptive
What’s the half life of insulin?
5-6 mins
What stimulates the secretion of insulin?
Blood sugar levels 90mg/dL
Congenital absence of 1 alpha hydroxylase leads to
Vit D resistance
In what type of diabetes mellitus is there weight loss?
Type 1
What hormones are used as steroidal contraceptives?
Estrogen and Progesterone
Or progesterone alone
What are the symptoms of deficiency of 17 alpha hydroxylase?
Lack of pubic and axillary hair in females
Deficiency of glucocorticoids
High levels of mineralocorticoids
In Depot intramuscular injection contraception, how long does it last?
2-3 months
How long can a subdermal contraceptive last?
< 2 years
Exogenous testosterone supports …….. but does not support …..
Androgen effects of sexual function and other targets of testosterone but does not support spermatogenesis
In menopause, the existing follicles are unresponsive to …….
FSH and LH
What are the characteristics of hotflushes?
Vasomotor instability Wide fluctuation in BP Fatigue Nervousness Emotional outburst Insomnia Palpitations Vertigo Headache and numbness Osteoporosis
What can be used to treat hot flushes?
Estrogen replacement therapy
Estrogen progesterone replacement therapy
Calcium supplements
Addison’s disease is characterized by…..
Weight loss
Chronic hypotension(addisonian crisis)
Elevated levels of ACTH leading to hyperpigmentation
Hyperkalaemia
What is the action of thyroid hormones on serum cholesterol?
It upregulates LDL receptors of the liver to transport cholesterol into the liver
Increases the uptake of cholesterol via steroid producing cells
Excretes sterol via the gut
How does stress affect thyroid hormone synthesis?
Stress decreases tsh levels cause glucocorticoids inhibit TRH
Whats the action of melatonin in humans?
it delays the onset of puberty by inhibiting the gonads
AG1 has ………….. amino acids while AG2 has …………… aa
10
8
in the dev of the gonads, 5th-6th week is for 7th-8th week is for 8th -12th week is for 10th-12th week is for
- dev of bipotential gonad
- sex determination and gonadal differentiation
- endocrine hormone secretion
- development of internal genitalia(testosterone and MIF dependent) and external genitalia(testosterone dependent only)
how long does spermatogenesis take?
72-74 days
GnRH is a peptide with how many aa?
10
what is the normal sperm count?
100-200million per ml
amount of sperm in a single ejaculate is 3-4ml
turner’s syndrome is … while kinefelter syndrome is ………
45X0
47XXY
characteristics of turner syndrome includes ……….
shorter than average
slightly larger necks
infertility
characteristics of turner syndrome includes ……….
shorter than average
slightly larger necks
infertility
characteristics of Klinefelter syndrome includes ……….
low testosterone production
reduced fertility or infertility
taller than average
moree breast tissue
granulosa cells secrete … while theca cells produce ………
inhibin and they also produce estradiol(under the action of FSH)
granulosa cells receive androstenedione made by the theca cells as their precursor for its synthesis
theca cells produce androstenedione from cholesterol under the action of LH
…… is the life saving hormone
Aldosterone
Estrogen has actions similar to what hormone? Cause it causes …….
Aldosterone
Salt and water retention