Specificity and Sensitivity of Cortisol-Induced Changes in Alpha Aminoisobutyric Acid Transport in Human Leukemic Small Lymphocytes and Leukemic Myeloblasts
AUTOR(ES)
Frengley, Patrick A.
RESUMO
We have examined the in vitro effect of glucocorticoid and nonglucocorticoid steroids on the transport of [3-14C]alpha aminoisobutyric acid (AIB) in lymphocytes from patients with chronic lymphocytic leukemia (CLL), and myeloblasts from patients with acute granulocytic leukemia (AGL). AIB uptake by CLL lymphocytes was markedly inhibited at 1.0 μM (52±2.1%) and slightly inhibited at 0.1 μM (17±3.0%) cortisol. A similar degree of inhibition developed at 50-fold lower concentrations of dexamethasone, indicating that the effect of these steroids on AIB accumulation parallels their glucocorticoid activity in vivo. In contrast, minimal or no inhibition was observed with steroids devoid of glucocorticoid activity (progesterone, testosterone, cortisone). 11-deoxycortisol, a nonglucocorticoid known to impede the binding of cortisol to cellular receptors in animal lymphocytes, failed to inhibit AIB uptake by CLL lymphocytes appreciably, but reduced the effect of cortisol to a statistically significant degree. Hence, cortisol-induced inhibition of AIB transport in CLL lymphocytes is related to its glucocorticoid activity and appears to require initial interaction with glucocorticoid-specific cellular receptors.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=302417Documentos Relacionados
- Alpha-aminoisobutyric acid transport in human leukemic lymphocytes: in vitro characteristics and inhibition by cortisol and cycloheximide
- Role of Estradiol in Cortisol-Induced Reduction of Luteinizing Hormone Pulse Frequency
- Effects of steriod hormones on human fibroblasts in vitro. II. Antagonism by androgens of cortisol-induced inhibition.
- Multicomponent analysis of amino acid transport in human lymphocytes. Diminished L-system transport in chronic leukemic B lymphocytes.
- Characteristics and energy requirements of an alpha-aminoisobutyric acid transport system in Streptococcus lactis.