Distribution of alpha-adrenergic receptors in the rabbit nephron.
In order to determine the distribution of alpha-adrenergic receptors within a nephron, a method was used to determine the specific binding of [3H]-prazosin to isolated fragments of rabbit renal tubules. When 10(-8) moles/liter [3H]-prazosin was incubated with proximal convoluted tubules, 61.4% of total binding was accounted for specific binding. The [3H]-prazosin binding to the proximal convoluted tubule was a linear function of the tubular length and reversible. It was inhibited with 10(-4) moles/liter phenoxybenzamine by about 60%, and with 10(-4) moles/liter norepinephrine by about 25%, but not with either atenolol or isoproterenol. No specific binding of [3H]-prazosin was observed in the proximal straight tubule and in the cortical collecting tubule. These data are in good agreement with the view that alpha-1 adrenergic receptors are mainly distributed in the proximal convoluted tubules.
D000818:Animals; D001262:Atenolol / Q000494:pharmacology; D005260:Female; D007545:Isoproterenol / Q000494:pharmacology; D007685:Kidney Tubules, Collecting / Q000187:drug effects / Q000294:innervation / Q000378:metabolism; D007687:Kidney Tubules, Proximal / Q000187:drug effects / Q000294:innervation / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology; D010643:Phenoxybenzamine / Q000494:pharmacology; D011224:Prazosin / Q000378:metabolism*; D011799:Quinazolines / Q000378:metabolism*; D011817:Rabbits; D011869:Radioligand Assay; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*; D014018:Tissue Distribution
D011799:Quinazolines; D011942:Receptors, Adrenergic, alpha; D010643:Phenoxybenzamine; D001262:Atenolol; D007545:Isoproterenol; D009638:Norepinephrine; D011224:Prazosin