Cosyntropin 250 mg

Cosyntropin 250 mcgsib haum mus rau biologically active 1-24 amino acid fragment ntawm adrenocorticotropic hormone (ACTH). Nws pom tau tias muaj zog khi rau lub peev xwm mus rau melanocortin 2 receptor (MC2R) nyob rau hauv lub zona fasciculata ntawm lub qog adrenal, nrog nws cov receptor affinity ncav cuag 1.5 npaug ntawm ntuj endogenous ACTH. Thaum noj ntawm tus qauv koob tshuaj 250 ug, tus neeg sawv cev tuaj yeem ua tiav qhov supraphysiological saturation concentration hauv cov hlab ntsha. Txhawm rau muab tso rau hauv qhov kev xav, qhov siab tshaj plaws ntawm lub cev ntawm ACTH hauv tib neeg lub cev yog ib txwm qis dua 100 pg / mL, thaum cov ntshav ntawm cov khoom muaj zog nce mus rau ntau dua 10⁴ pg / mL tom qab 250 ug koob.

Nws kuj tseem ua rau cov kws kho mob tuaj yeem ntes txawm tias qhov hloov maj mam thiab me me ntawm adrenal dysfunctions uas yog ib qho nyuaj rau kev kuaj xyuas niaj hnub, xa qhov raug siab rau kev kuaj mob auxiliary.Cold door desensitization effect: Hyperphysiological concentrations induce transient endocytosis thiab phosphorylation ntawm MC2R (peak receptors tom qab 6-6 feeb) ACTH thiab tsim kev hloov pauv ntawm adrenal desensitization. Cov kev sim tsiaj tau pom tias 2 teev tom qab kev tswj hwm ntawm 250 μ g, lub qog adrenal cov lus teb rau theem nrab ACTH stimulation poob los ntawm 40%, thiab maj mam rov qab los tom qab 24 teev. Cov nyhuv no feem ntau raug saib xyuas hauv kev kuaj mob niaj hnub, tab sis tseem ceeb heev hauv kev rov ua kom rov ua haujlwm thiab HPA axis muaj nuj nqi cuam tshuam.

Ib nrab neej thiab concentration nkhaus:

The half-life of intravenous administration is 15-20 minutes, while intramuscular injection takes 30-45 minutes. The peak blood concentration (>10 ^ 4 pg / mL) tau mus txog hauv 30 feeb, thiab poob qis hauv 60 feeb ntawm lub cev.

Tsis tshua muaj feature:

Txawm hais tias cov tshuaj tau tshem tawm sai sai, qhov ua kom muaj zog ntawm adrenal ua haujlwm ntev li 48-72 teev - txhawb nqa kev qhia ntawm cortisol synthase los ntawm kev hloov pauv ntawm epigenetic (histone acetylation), ua rau ntev - kev ua haujlwm ntev ntev uas txawv ntawm cov tshuaj siv tshuaj rau lub sijhawm luv.

Tag nrho txoj kev qhib:

Ib txhij txhawb nqa tag nrho cov txheej txheem ntawm kev thauj cov roj cholesterol, pregnenolone synthesis, thiab 11 deoxycortisol hloov dua siab tshiab rau cortisol, tsis yog ib qho txuas - cov pa physiological ACTH tsuas yog ua rau ib feem ntawm txoj kev,

Thiab 250 μ g tuaj yeem ua txhaum los ntawm "enzyme kev ua haujlwm hauv lub raj mis" los ntawm kev mob HPA axis inhibition.

Inhibition ntawm aldosterone cross secretion: 250 μ g muaj affinity tsawg rau MC2R nyob rau hauv lub zona pellucida thiab tsuas yog me ntsis nkoos aldosterone (<10%), without interfering with the renin-angiotensin system (RAAS), ensuring specificity in HPA axis evaluation - distinct from natural ACTH (mildly stimulating aldosterone).

250 μg saturation activation tuaj yeem kuaj pom tsis txaus cortisol (<500mol/L) and decreased increment (<200nmol/L), confirming occult central inhibition.Moderate to severe inhibition: Adrenal atrophy (long-term ACTH deficiency) - no significant increase in cortisol after 250 μ g stimulation (<300nmol/L), diagnosed with complete central inhibition; Accurate differentiation between combined basal ACTH (low/normal low) and primary AI (significantly elevated basal ACTH).The unpopular recognition of 'insufficient stress reserve-Some patients have normal basal cortisol levels (350-500nmol/L), but insufficient secretion under stress -250 μ g simulated extreme stress ACTH levels. If the peak value is less than 550nmol/L, it indicates a deficiency in stress reserve and is a hidden HPA axis inhibition, which can easily induce adrenal crisis during infection and surgery.

The increase, peak, and peak time of cortisol after 250 μ g stimulation can accurately predict the recovery rate and reversibility of HPA axis inhibition:Peak value of 500-550nmol/L, increment>250nmol / L: me me reversible inhibition, zoo rov qab 1-3 lub hlis tom qab txiav; Peak tus nqi ntawm 300-500 nmol / L, nce ntawm 100-250 nmol / L: nruab nrab reversible inhibition, rov qab nyob rau hauv 3-6 hli.Peak<300nmol/L, increment<100nmol/L: severe/irreversible inhibition, requiring long-term replacement, recovery>12 lub hlis.Mechanism: Lub ncov ntawm cortisol tom qab ua kom muaj zog ntawm 250 μ g ncaj qha cuam tshuam txog cov qog adrenal cortex, MC2R ntom ntom, thiab tag nrho cov kev ua ntawm synthase, thiab yog ib qho tseem ceeb ntawm cov cim cim rau HPA axis rov qab.