Physiology Flashcards
What hormones are synthesised by the kidney?
Renin
1,25 dihydroxyvitamin D
Erythropoietin
Effect of acidosis on k+ and chloride
Acidosis causes potassium retention and a rise in chloride.
Anion gap maintained.
Oestrogens cause…
Hypertrophy of the uterus and lower genital tract
Rhythmical contraction of the Fallopian tubes
Proliferation of vaginal stratified cells and increased glycogen content
Inhibition of prolactin release
Effect of thyroid releasing hormone on prolactin secretion
Stimulation
What stimulates prolactin release
Thyrotrophin releasing hormone
Insulin
Dopamine antagonists (metoclopramide, domperidone)
Suckling
What does prostaglandin f2 alpha do?
Antagonises progesterone activity.
Uterine contraction and bronchoconstriction.
What is beriberi a deficiency of
Thiamine
Cyanocobalamin deficiency causes what
B12 deficiency anaemia = macrocytic
What does niacin deficiency cause
B3 - pellagra
What condition is the effect of folate deficiency
Macrocytic anaemia
What is scurvy a deficiency of
Acscorbic acid = vit c
Where is growth hormone produced from
Pituitary gland
What hormones regulate growth hormone secretion
Growth hormone releasing hormone
Growth hormone inhibiting hormone (somatostatin)
Produced by the hypothalamus
What is the effect of blood glucose levels on growth hormone
Blood glucose levels fall and trigger the secretion of growth hormone releasing hormone to rerelease stored growth hormone
What happens to maternal level of placental growth hormone during pregnancy
Increase throughout pregnancy from week 8 to reach a peak at 35 weeks
When may levels of sex hormone binding globulin be decreased
Obesity Hypothyroidism Androgen use Nephrotic syndrome Cushing's disease Acromegally
When may levels of sex hormone binding globulin be increased
Hepatic Cirrhosis
Hyperthyroidism
Oestrogen use
Effect of low oestrogen on bone
Decreased absorption of calcium and vit D
Thinning trabecular bone, osteoporosis
Increased risk of fractures
What happens immediately after large haemorrhage
Anaerobic glycolysis due to decreased perfusion Carotid chemoreceptors stimulated Coronary vasodilation Fall in pulse pressure ADH secretion and thirst
What pathway is assessed by the prothrombin time
Extrinsic pathway - factors 7, 10, 5 and 2
How does warfarin produce its effects
Interferes with vitamin K metabolism
Inhibits the Alpha carboxylation of factors two, seven, nine, 10
Prolongs prothrombin time
How does low molecular weight heparin exert its effects
Factor 10a inhibitor
What hormones increase plasma glucose
Growth hormone
Adrenaline
Glucagon
Corticosteroids
What hormone deficiency causes hot flushes
Oestrogen
Leptin produced by placental syncytiotrophoblast is involved in what processes in pregnancy
Implantation, proliferation of cytotrophoblasts and transfer of nutrients across the placenta
Presentation of acute adrenocortical insufficiency (addisonian crisis)
Weakness Nausea and vomiting Abdominal pain Hypotension Fever
Hyponatraemia
Hyperkalaemia
Acidosis
Hypoglycaemia
What other hormone is growth hormone structurally similar to?
Prolactin
Site of calcitonin production
Parafollicular cells of thyroid
Effect of calcitonin
Reduce blood levels of calcium. (Cali-tone-it down)
Opposes effect of parathyroid hormone.
Metabolic effects of growth hormone
Enhances aminoacid transport
Decreases utilisation of protein
Increased glycogen deposition
Increased blood glucose concentration
Where is human chorionic gonadotropin produced
Outer layer of the blastocyst
Placenta
hCG effect on thyroid
TSH like effect
What happens to levels of sex hormone binding globulin in pregnancy
Increase
What hormone binds to sex hormone binding globulin
Testosterone
Effect of aldosterone on the kidney
Conserve sodium
Excrete potassium
What is the main regulator of aldosterone secretion
Angiotensin II
What does high free T4 and high TSH suggest
Pituitary TSH secreting tumour
Causes of metabolic acidosis
DKA Severe diarrhoea Lactic Acidosis Liver failure Starvation Uraemia
ADH secretion is inhibited by
Dilution Cold Increased BP Alcohol Tetracyclines
ADH secretion is increased by
Barbiturates
SSRIs
Sulphonylureas
What are platelets made off
Membrane encapsulated fragments of megakaryocytes
Formed in bone marrow
No nucleus
What substances to platelets release
Nitric oxide
Thromboxane
Prostaglandins
Platelet lifespan
9-10 days
How is Bilirubin produced
Breakdown product of haem
How is bilirubin transported
bound to Albumin
Features of phaeochromocytoma
Panic attacks Sweating Anxiety Tremors Palpitations Variable hypertension Hyperglycaemia
