Effects of beta-adrenoceptor blockade on the phenotypic characteristics of thymocytes and peripheral blood lymphocytes.

Immunology Research Center Branislav Janković, Institute of Immunology and Virology Torlak, Belgrade, Serbia and Montenegro.
International Journal of Neuroscience (Impact Factor: 1.52). 01/2004; 113(12):1653-73. DOI: 10.1080/00207450390245216
Source: PubMed


The study revealed that beta-adrenoceptor blockade with propranolol (0.40 mg/100 g/day, s.c.) in adult male DA rats: (i) increased the thymocyte proliferation and apoptosis, (ii) caused disturbances in kinetics of T cell differentiation leading to distinguishable changes in relative proportion of thymocytes at distinct maturational steps and to an expansion of the most mature single positive (CD4+, CD8+) thymocyte pool, (iii) affected the relative proportion of neither CD4+ nor CD8+ peripheral blood lymphocytes (PBL), and (iv) augmented the relative number of CD8+CD25+ cells. Thus, the results suggest the role of beta-adrenoceptors in fine-tuning of T cell maturation, and, possibly, distribution and activation of distinct PBL subsets.

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    • "Rats were treated with propranolol hydrochloride (0.40 mg/ 100 g body weight /day) for 4 or 16 days starting 3 days prior to the induction of experimental allergic encephalomyelitis (day 0). The dose was chosen on the basis of our previous results that indicated that propranolol effectively modulated T-cell maturation and phenotypic characteristics of peripheral blood lymphocytes from Dark Agouti rats (Rauški et al., 2003). "
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