Exercise-induced changes in beta-adrenergic-receptor mRNA level measured by competitive RT-PCR.
Competitive reverse transcription-polymerase chain reaction (RT-PCR) analysis was used to clarify whether dynamic exercise-induced increases in beta-adrenergic-receptor (beta-AR) number in human lymphocytes are accompanied by increases in the beta-AR mRNA level. Sixteen healthy subjects performed cycle ergometry until exhaustion. Before and immediately after exercise, peripheral blood was drawn from a forearm vein for preparation of lymphocytes. Both the beta-AR mRNA level and the beta-AR number were significantly increased by exercise. The changes in beta-AR mRNA level and beta-AR number were significantly correlated (r = 0.63, P < 0.01). This finding suggests that a rapid increase in beta-AR mRNA level might be an early adaptive response of the sympathetic nervous system to dynamic exercise. In vitro incubation of lymphocytes with epinephrine had no effect on beta-AR mRNA levels, nor did adenosine 3',5'-cyclic monophosphate, protein kinase C, or intracellular Ca2+ increase the beta-AR mRNA level in vitro. Therefore, it appears that other mechanisms underlie the exercise-induced elevation of beta-AR mRNA levels in human lymphocytes.
Fujii
N
N
Gene Experiment Center, University of Tsukuba, Japan.
Shibata
T
T
Homma
S
S
Ikegami
H
H
Murakami
K
K
Miyazaki
H
H
D000328:Adult; D015444:Exercise; D005080:Exercise Test; D006728:Hormones / Q000097:blood; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D010807:Physical Endurance; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism*; D011943:Receptors, Adrenergic, beta / Q000235:genetics*; D014158:Transcription, Genetic
D006728:Hormones; D012333:RNA, Messenger; D011943:Receptors, Adrenergic, beta