pop endi Flashcards
a) What is the safe range of BMI (1)?
18.5 > BMI > 25
b) A man is 98 kg and 175 cm tall. What is his BMI? (2 marks, remember units)
98/1.75^2 units are kg/m^2
c) In the obese, what is the main energy storage chemical? (1)
Fat/Lipids/Adipose tissue
d) What effect does insulin have on:
i) Adipose tissue lipolysis?
ii) Hepatic glucose management? (2)
iii) Production of ketones? (1)
iv) Muscle glucose intake (name receptor)? (2)
i) Decrease lipolysis
ii) Decreases hepatic glucose output (Decrease hepatic gluconeogenesis / decrease hepatic glycogenolysis / increase glycogenesis
iii) Decrease ketogenesis (No need to synthesis ketones to use as energy when there is already plenty of glucose available)
iv) GLUT-4, Increase muscle uptake
What is the receptor for oxytocin and what are its target tissues?
OXTR
Myometrial cells of the uterus
Myoepithelial cells of the mammary gland
What is the receptors for vasopressin and what are its target tissues?
V1a: Arterial/arteriolar smooth muscle
Hepatocytes (glycogenolysis)
CNS neurones
V1b: Adenohypophysial corticotrophs
V2:
Kidney collecting duct cells
Endothelial cells??
Factor VIII and Von Willbrandt factor??
a) Draw a diagram indicating all the different parts of the adrenal glands and what hormones each part secretes (4)
Adrenal Cortex:
Zona Glomerulosa – Aldosterone
Zona Fasciculata – Cortisol
Zona Reticularis – Sex hormones - androgens, oestrogen
Adrenal Medulla: – Adrenaline, noradrenaline, dopamine
List 3 hormonal components of the hypothalamo-adenohypophysial-adrenal axis (3 marks)
Somatotrophin, prolactin, TSH, LH, FSH, Corticotrophin
CRH (and VP for cortisol) -corticotrophin/ACTH - cortisol
FROM ANOTHER: Hypothalamus - Corticotrophin releasing hormone
Adenohypophysis - ACTH
Adrenal Glands - Cortisol
What is failure of the adrenal glands known as? Give two reasons why it occurs (3 marks)
Addison’s disease
Adrenal TB and autoimmune disease of the adrenals
Worlds biggest cause of TB
a) Name 2 tissues that produce androgens (1)
Leydig cells – mainly testosterone and some androgens
Theca cells - androgens
Tissues = adrenal glands and gonads (testes and ovaries)
(Also skin, brain, liver, prostate, seminal vesicles)
b) Describe the effects of testosterone in i) virilisation; ii) anabolism (2x2 marks)
The biological development of sex differences, changes that make a male body different from a female body.
i) Increases virilisation by stimulating growth and development of male genitalia, deeper voice, growth of pubic hair.
ii) Causes protein anabolism; decrease fat anabolism.
c) How do excess androgens cause infertility in males?
Prolactinoma – a benign tumour in the pituitary gland, causes excess prolactin to be produced by pituitary gland.
Prolactin inhibits Gonadotropin releasing hormone, thereby inhibiting spermatogenesis.
NB: Androgens produced by the Leydig cells (ie testosterone) exert negative feedback effects at the pituitary (LH, FSH) and hypothalamus level (GnRH). Too much androgens would inhibit the release of GnRH and therefore LH and FSH. This means that the Leydig cells stop producing androgens (testosterone) which is crucial for spermatogenesis.
No spermatogenesis = no spermatozoa (mature sperm) and therefore the male cannot conceive as only mature sperm can fertilise the egg. (Sertoli + FSH system also needed for germ cell dev).
d) Identify other symptoms of excess androgens
Women with high levels of testosterone have polycystic ovary syndrome, characterised by amenorrhoea or oligomenorrhoea, infertility, blood sugar disorders, sometimes acne and excess hair growth.
• Aggression, competitiveness, mood swings, depression, low sperm count
• Deeper voice, increase in body hair, muscle mass
b) Name a stress hormone and 2 discrete physiological responses to it. (3)
Cortisol • Peripheral protein catabolism • Hepatic gluconeogenesis • Increased blood [glucose] • Fat metabolism (lipolysis in adipose tissue)
c) Name the condition related to adrenal failure and two common causes? (2)
Addison’s disease – adrenal TB, autoimmune disease of the adrenals
d) Immediate Treatment for acute adrenal failure. (1)
Injection of hydrocortisone (synthetic cortisol) in a vein
f) What hormone is released when blood glucose is high? How should it be delivered to patients?
Insulin
Injection into fatty tissue underskin (subcutaneous fat) in fatty area – thigh, abdomen.
NB: When blood glucose low: intramuscular injection of glucagon.
Two different types of cells that are developing in the ovarian follicle
Theca and granulosa cells
- What hormones do follicular and luteal synthesise?
Follicular: LH stimulates the thecal cells to produce androgens. The androgens diffuse into the granulosa cells. Under the influence of FSH, the granulosa cells produce aromatase, which converts androgens into oestrogen.
Luteal: LH and FSH cause the corpus luteum (produced by granulosa cells) to produce progesterone and oestrogens (less so).
Describe the cells of the testes and its functions of each.
Sertoli cells:
• Form seminiferous tubules
• Synthesise FSH and androgen receptors
• In response to FSH, molecules such as inhibin are produced
Leydig cells:
• Produce testosterone
• Synthesise LH receptors
• In response to LH they produce androgens
b) Name the hormone which stimulates aldosterone secretion (1)
Angiotensin II
c) Describe each part of the adrenal cortex and indicate what each part secretes (3)
Zona Glomerulosa – Aldosterone
Zona Fasciculata – Cortisol
Zona Reticularis – Sex hormones
(Last two are glucocorticoids)
d) Name two uses of pharmacological doses of cortisol (2)
Anti-inflammatory action
Immunosuppressive action
Anti-allergic action
a) Identify four hormones that elevate the plasma glucose concentration.
Cortisol
Glucagon
Catecholamines (adrenaline)
Somatotrophin
b) List the major physiological stimulant to insulin secretion and two other stimulants.
b) Increased plasma Glucose concentration (1mark) (Not FFA)
Others, positive: amino acid concentration, glucagon, some gut hormones, parasympathetic, sympathetic b receptors (any two = 2 marks)
c) What is the main stimulus to glucagon secretion?
c) Low plasma glucose (1 mark)
d) A high plasma glucose concentration and osmotic symptoms (glycosuria and polydipsia) are found in types 1 and 2 diabetes mellitus. State what common sign and simple biochemical test suggest the absolute insulin deficiency of type 1 diabetes mellitus?
d) Weight loss, Ketones (in urine) (2 marks)
Describe a test for primary hyperthyroidism and state what you would find (2)
A thyroid-stimulating hormone (TSH) test, which is a blood test that measures your levels of TSH.
High thyroxine level and 0 TSH.
i) Describe a test for primary hypothyroidism and state what you would find (2)
TSH test – take a sample of blood and measure level of TSH (measuring TSH – thyroid stimulating hormone, thyrotropin)
Low thyroxine level and high TSH level.
How is primary hypothyroidism treated? (1)
Replace thyroxine via tablets
Why is there increased pigmentation in those with adrenal failure? (3)
- Adrenal glands are failing. ACTH levels will rise in order to try and make the adrenal glands produce more cortisol.
- POMC is a precursor to ACTH as well as MSH (Melanin Stimulating Hormone). If ACTH levels high then so too are MSH which means that skin will darken.
What is the immediate treatment for someone suffering from an Addissonian crisis? (3)
- Rehydrate with normal saline
- Give dextrose to prevent hypoglycaemia
- Give hydrocortisone