title: Antidiuretic agonism and antagonism of some O-alkylated analogues of vasopressin containing 2-O-alkylated tyrosine.
abstract: A series of 2-O-alkylated tyrosine analogues of lysine-vasopressin and desamino-lysine and arginine-vasopressin were synthesized and tested for antidiuretic activity in the water-loaded anaesthetized rat. The analogues displayed only weak antidiuretic activities. When they were infused in the rats together with lysine vasopressin it was found that 1-deamino-[2-O-ethyltyrosine]-lysine-vasopressin inhibited the vasopressin-induced antidiuretic response. The antagonistic properties were further evaluated in long-term experiments on conscious non-hydrated rats with implanted minipumps. The analogues inhibited the vasopressin-induced antidiuresis at antagonist:agonist ratios of 0.5 and 1.0.
mesh_terms: D000478:Alkylation; D000758:Anesthesia; D000818:Animals; D004231:Diuresis / Q000187:drug effects*; D008236:Lypressin / Q000031:analogs & derivatives; D008297:Male; D051381:Rats; D013329:Structure-Activity Relationship; D014443:Tyrosine; D014667:Vasopressins / Q000037:antagonists & inhibitors / Q000494:pharmacology
chemical_list: D014667:Vasopressins; D014443:Tyrosine; D008236:Lypressin