P: revision questions Flashcards
the size of which blood vessel is important in determining peripheral vascular resistance?
tone of ARTERIOLES
why is systolic blood pressure higher than diastolic?
as systolic pressure needs to be high enough to propel blood to the tissues, where as diastolic is just minimum resting pressue when heart relaxes to
what are the normal mechanisms that regulate blood pressure to keep it within normal range?
Baroreceptors** in carotid sinuses & aortic arch: stimulated when BP rises, inhibited when BP lowers
- > brain
- > RAS** = Renin Angiotension System
- > vasodialation/constriction, increase or decrease CO
- > Atrial Natriuretic Peptide**
- > homeostasis returned
what does systemic hypertension normally present as?
when BP is persistently higher than 140/90
what can secondary hypertension result from?
Can arise from any condition that influences BP regulation
- renal: sodium excretion, fluid retention
- endocrine: response of arterioles to sympathetic stimulation - over production of cortisul, aldosterone of ACTH
- renal artery stenosis: decrease B supply to kidney => renin => angiotension II => vasoconstriction => increase BP
risk factors of hypertension?
enviro/lifestyle:
- abdominal obesity
- insulin resistance/type 2 diabetes
- inactivity
- alco
principle mechanisms of cell injury?
1) reduced ATP
2) mitochondiral damage
3) influx Ca
4) increased Reactive Oxygen Species
5) loss of membrane integrity
6) DNA damage, protein misfolding
igG?
Vaccination
forms antibody-antigen complex(binds to antigen) which leads to it being phagocytosed, they have good memory, secondary large response
igM?
first response expressed by B cells, same response/magnitude errytime
igE
allergies - hay fever, ASTHMA
immunity to parasite infections
Hypersensitivity 1!
igA?
secreted across mucus membranes
igD?
expressed on naive B cells
hypersensitivity 1 is mediated by?
igE mediated
igE bind to mast cells
involved in anaphylactic reactions eg. asthma
hypersensitivity 2 mediated by?
igG mediated
- cytotoxic
antibodies produced by the normal immune response bind to antigens on a patients own cells
hypersensitivity 3 mediated by?
immune complex mediated
- damaging inflammation
hypersensitivity 4 mediated by?
cell mediated
how can chronic hypertension affect blood vessels?
atherosclerosis
hyaline arteriolsclerosis
benign nephrosclerosis
-> basically thickening of wall due to deposition of plasma proteins/extracellular matrix production, smooth muscle atrophy, scarring
effect of chronic hypertension on heart?
coronary artery disease, ischaemia, angina,
increased afterload on left ventricle leading to concentric left ventricular hypertrophy..impairing heart muscle function.. possible heart failure
chronic hypertension effect on retina?
hyaline arteriolsclerosis damages arterioles within eye, then can rupture causing haemorrhages/small infarcts.
=> cotton wall spots
negative feedback
when a rise in a particular hormone is sensed by receptors in the body and control centers then counteract heighten levels by either turning off stimulus that creates it or release another hormone that counteracts it
define apoptosis?
controlled by AUTODIGESTION of cell components due to activation of ENDOGENOUS enzymes
define necrosis?
unregulated enzymatic digestion of cell components, loss of membrane integrity with uncontrolled release of products of cell death into the intracellular space, initiation of inflammation response
hormones of anterior pituitary:
FSH & LH = testes of male, ovaries of female test, estro, progesterone
GH -> liver -> somatomedins => bone/muscle/other tissues
PRL = mammary glands
ACTH -> adrenal glands => steroid hormones
TSH -> thyroid gland => thyroid hormones
hormones of posterior pituitary?
ADH = kidneys
OXT = smooth muscle men = ductus deferens/prostate
women = uterine and mammary glands
anterior hypopituitarism?
epithelial cells, kinda secondary, hypothalamus releases hormone
GH deficiency
ACTH deficiency which leads to decreased adrenal production in adrenal cortex => AETIOLOGY => goitre
DECREASED T3 & T4,
posterior hypopituitarism?
posterior neurons cells
hormones made in hypothalamus,
neurogenic diabetes insipidus??
ADH effect on kidneys??
what is hypo/hyper pituitarism mostly due to?
tumours/lesions, infections etc.
anterior hyperpituitarism?
ADEMOMA of any hormones except TSH
increase in GH….gigantism in children, acromegaly in adults,
PRL - hyperprolactinaemia..lactotrope adenoma
ACTH - ..excessive adrenal hormone CUSHINGS disease
FSH & LH = gonadotrope adenoma, postmenopausal women
posterior hyperpituitarism?
syndrome of inappropriate ADH secretion
Hypothyroidism
Hashimotos disease
AUTOIMMUNE
decreased T3&T4, increased TSH
can result in goitre
Hyperthyroidism:
Graves disease
AUTOIMMUNE
increased T4
thyroid hormone effect on the following:
metabolic, GIT, CVS & neuromuscular
metabolic = increase basal, temp GIT = glucose catabolism, protein synthesis, lipidosis CVS = normal cardiac fuction neuromuscular = normal neuronal function adults/development in fetus, normal function and development of bone and skeleton
symptoms/signs expected from hyperthyroidism?
- increase in BMR resulting in weightloss
- decrease in lipidosis, and breakdown of glucose therefore low energy & fatigue
- tremor
- exophthalmos - bulging eyes
- goiter
what is the most common CAUSE of hyperthyroidism?
graves disease - autoimmune attack of thyroid gland
signs/symptoms of hypothyroidism?
- depression & forgetfullness
- dry skin(opposite of sweating)
- weight gain
- goiter
most common cause of HYPOthyroidism?
hashimotos disease!
increased TSH and decreased T4&T3
and iodine deficiency
insulin:
stimulates synthesis of glycogen from glucose
STORES
Glucagon:
breaks down glycogen into glucose
myocardial infarction typically occurs due to?
development of an occlusive thrombosis over a pre-existing atherosclerotic plaque
- arrhythmias may arise
4 inflammatory exudate and what each contains?
1) purulent = neutrophils and bacteria
2) fibrinous = fibrin + leukocytes and fluid
3) serous = mainly fluid small amount
4) haemorrhagic = RBC, fibrin, fluid, leukocytes
what is granulation tissue?
what does it consist of?
intermediately tissue of repair, during healing via fibrosis
macrophages(remove debris), fibroblasts(produce collagen) an newly formed blood vessels(to provide nutrients to the above cells)
osteophyte formation is for which bone disease?
osteoarthritis
difference between osteoporosis and osteoarthritis?
osteoporosis = mass and density decrease osteoarthritis = articular cartilage through FRICTION breakdown, chondrocytes, osteophytes
gluconenogenesis definition
production of glucose
breaking down of glycogen to form glucose
