Growth properties and receptor expression in vascular smooth muscle cells from hypertensive rats.
The objective of this study was to evaluate the growth properties and receptor expression in aorta-ring derived smooth muscle cells (SMCs) cultured from control (WKY) and spontaneously hypertensive rats (SHR). SHR-SMCs exhibited a 3-4 day lag period before migrating. In addition, SHR-SMCs had a significantly higher growth rate, shorter population doubling time and higher saturation density level characteristics that were retained at higher passage levels. beta-adrenergic and angiotensin (All) receptors were measured using iodocyanopindolol (ICYP) and [3H]-All, respectively. All receptor expression was similar in both WKY and SHR-SMC cultures. WKY-SMCs exhibited little ICYP binding (Bmax 8.27 +/- 2.0 fmol/mg) while SHR-SMC binding capacity was 8 fold higher (Bmax 65 +/- 9.2 fmol/mg). In addition, the responsiveness of the beta-receptor, as assessed by adenylyl cyclase stimulation, was similar for WKY and SHR-SMCs. These data suggest that factors regulating SMC receptor expression in vitro are selective since All and adrenergic receptor densities exhibit different responses to hypertension.
Grammas
P
P
Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City 73190.
Diglio
C
C
Giacomelli
F
F
Wiener
J
J
D000818:Animals; D002455:Cell Division; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D006973:Hypertension / Q000378:metabolism* / Q000473:pathology*; D007700:Kinetics; D009131:Muscle, Smooth, Vascular / Q000378:metabolism* / Q000473:pathology*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D011945:Receptors, Angiotensin / Q000378:metabolism
D011943:Receptors, Adrenergic, beta; D011945:Receptors, Angiotensin; D000242:Cyclic AMP