@article{oai:niigata-u.repo.nii.ac.jp:00006627,
 author = {Watanabe, Kenichi and Shibata, Akira and Wakabayashi, Hiroyuki and Shimada, Kenji and Tsuchihashi, Hiroshi and Kinami, Junji and Nagatomo, Takafumi},
 issue = {2},
 journal = {Acta medica et biologica, Acta medica et biologica},
 month = {Jun},
 note = {Values of Kd and Bmax in ^3H-prazosin, ^<125>I-iodocyanopindolol and ^3H-nitrendipine bindings to α_1- and β_1-adrenergic receptors and Ca^<2+> binding sites of the myocardium of 2,6,　and 16 week-old Wistar Kyoto normotensive Rats (WKY) and spontaneously hypertensive rats (SHR) were compared using a radioligand binding assay method. The catecholamine concentration in the myocardium of both WKY and SHR was also determined. Results obtained as follows: (1) decrease in the Bmax values in α_1- and β_1-adrenoceptors of WKY and SHR during growth was observed; (2) values of Bmax in β_1-adrenoceptors of 16 week-old SHR higher than those of WKY were observed, and in contrast low Kd values of α_1-adrenoceptors in 16 week-old SHRs were　observed; (3) no alterations in the Ca^<2+> binding sites in myocardium of both groups were observed during growth and between WKY and SHR; (4) in addition, the increase of norepinephrine concentration in　the myocardium of both WKY and SHR during growth was observed and that of 16 week-old SHR was higher than that of WKY. The present study therefore implies that significant high norepinephrine　concentration in the myocardium of 16 week-old SHR results in changes in β_1-adrenoceptors binding sites, suggesting that defects of membranes of myocardium of SHR may occur.},
 pages = {69--74},
 title = {Changes in Cardiac α_1-and β_1-adrenergic Receptors and Ca^<2+> Binding Sites in the Myocardium of SHR},
 volume = {38},
 year = {1990}
}