Stereospecificity of beta-adrenoceptor blockade and renal vasodilatation by tertatolol.
To investigate the stereospecificity of beta-adrenoceptor blockade and renal vasodilatation by tertatolol, the regional hemodynamic effects of the 2 stereo-isomers of tertatolol (d-tertatolol and l-tertatolol) were compared in conscious spontaneously hypertensive rats. Furthermore, the effects of a combination of d-tertatolol and dl-propranolol were studied. l-Tertatolol and the combination of beta-blockers lowered heart rate and caused an early increase and a late decrease of blood pressure. l-Tertatolol, but not the combination of dl-propranolol and d-tertatolol, decreased renal resistance at 3-4 hr after injection. Injections of d-tertatolol alone did not cause any effect. Since effects of l-tertatolol are fully comparable to effects previously observed with dl-tertatolol, and d-tertatolol was devoid of any effects, both alone and in combination with dl-propranolol, we conclude that both beta-adrenoceptor blockade and renal vasodilatation are stereospecific for the l-isomer of tertatolol.
Smits
J F
JF
Department of Pharmacology, University of Limburg, Maastricht, The Netherlands.
Zeegers
H H
HH
Struyker-Boudier
H A
HA
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D008297:Male; D011412:Propanolamines / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D012039:Regional Blood Flow / Q000187:drug effects; D012079:Renal Circulation / Q000187:drug effects*; D013152:Splanchnic Circulation / Q000187:drug effects; D013237:Stereoisomerism; D013876:Thiophenes; D014664:Vasodilation / Q000187:drug effects*
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D013876:Thiophenes; D011433:Propranolol; C005632:tertatolol