Thyroid Flashcards
Type of transporters and their inhibitors
NIS inhibited by thiyocyanate
Thyroid perpxidase by PTU bad methimazole
Deiodinase( contain seleno cysteine)
Action of thyroxin
- Calorigenic
- increase O2 consumption of almost all metabolically active tissue( except brain uterus testis LN spleen ant pit)
- increase BMR ( catabolism of proteins and fat)
- increase the activity of NaK ATPase
2. CVS Direct action and via catecholmaines 3.Nervous system 4: catecholamines 5. Growth 6.
Thyroxin HR complex action on genes
Enhance Alpha myosin activity B adrendrigc receptors Ca ATPase NaK atpase
Inhibit
Beta myosin activity
Adenlyl cyclase
NaCa exchanger
T1/2 Of T4 And T3
T3 - 2 days
T4 - 7 days
List diffuse goiters
Graves
Hashimotos
Dequeveriens
Differentiating an active and inactive Thyroid
State. Epith. Colloid
Resting squamous. abundant
Active. Cuboidal. Moderate
Highly. Low columnar Scanty
Active
Hashimotos Thyroiditis features
Diffuse goiter
Antithyroid peroxidase AB
May slightly increase the risk of pap CA (5%)
Not painful
Associated with other auto immune diseases
Hypothyroidism features General Hair Eyes Ears Skin Heart Muscles Genitalia Anal Legs
General
- tired , weight gain , cold intolerance, goiter (deep voice )
Mental depression psychosis coma poor memory
Hair - dry thin hair, loss of eyebrows
Eyes puffy eyes , periorbital oedema
Ears deafness
Skin dry coarse
Heart HT Heart Failure brady pericardial effusion
Muscles arthralgia myalgia proximal myopathy slow relaxing reflexes
Genitalia poor libido menoragia hyperprolactinaemia
Anal constipation
Legs Hands carpal tunnel , oedema
Hyperthyroidism features General Hair Eyes Ears Skin Heart Muscles Genitalia Anal Legs
General tremor weight loss restless malaise tall breathless heat intolerance
Hair
Eyes peri orbital edema , ophthalmoplagia, conjunctival edema
Ears
Skin itching sweating
Heart palpitations Tachy , atrial fibrillation , warm vasodilated peripheries , HT, heart failure
Muscles stiff, proximal myopathy , oncholysis
Genitalia loss of libido gynecomastia Oligomenorrhea
GI vomiting , diarrhea
Legs hands Palmer erythema , pretibial myxedema
Thyroid hormone and ADH and AST levels
Hypothyroidism -> fluid retention -> ADH suppressed -> hyponatermia
Increased serum AST Levels
Carcinoma
Commenest
Blood spread
Papillary 70% follicular 20%
Papillary lymphatic spreads
Follicular hematogenous spread
T1/2 Of carbimazole And PTU
Carb 6 hours
PTU 2 hours
Functions of TSH
- Increase iodide binding
- Synthesis of iodithyrosine
- Secretes thyroglobulin to colloid
- Endocytosis of colloid
- Synthesis of T3 and T4
