title: Arginine vasopressin (AVP) replacement of helper cell requirement in IFN-gamma production. Evidence for a novel AVP receptor on mouse lymphocytes.
abstract: Arginine vasopressin (AVP), a nine-amino acid neurohypophyseal hormone, is capable of replacing the helper cell requirement for IFN-gamma production by Lyt-2+ mouse splenic lymphocytes. We present data here showing that the AVP helper signal occurs via interaction with a novel R on splenic lymphocytes and involves primarily the N-terminal six-amino acid cyclic ring (pressinoic acid) with the C-terminal three-amino acid end of AVP playing a minor role. Pressinoic acid was capable of providing help at concentrations similar to those of AVP, whereas oxytocin and isoleucine pressinoic acid were 10- and 100-fold less effective, respectively. Isoleucine pressinoic acid has the same structure as pressinoic acid except for the substitution of isoleucine for phenylalanine in position 3 of the sequence. Consistent with the function data, R binding competitions with splenic lymphocyte membrane preparations showed that AVP and pressinoic acid competed similarly with [3H]AVP, whereas oxytocin and isoleucine pressinoic acid were much less effective competitors. Further characterization of the AVP lymphocyte R was performed using AVP analogues having well defined agonist and antagonist activities on either V1 (vasopressor) R or V2 (antidiuretic) R. The AVP helper signal was blocked by the V1 antagonist [d(CH2)1(5) Tyr(methyl)]AVP but not by another V1 antagonist, [d(CH2)1(5)D-Tyr(ethyl)2Val4]AVP. Both V1-R antagonists were able to block [3H]AVP binding to the V1-R on liver cells, whereas only the V1 antagonist that blocked AVP help was able to compete effectively for the spleen AVP-R. Neither a V2 agonist nor a V2 antagonist had any effect on AVP help in IFN-gamma production. These data strongly indicate the presence of a novel AVP-R on spleen lymphocytes, which is related to the classic V1-R on liver cell membranes.
authors.affiliation: Department of Comparative and Experimental Pathology, University of Florida, Gainesville 32610.
authors.forename: B A
authors.initials: BA
authors.lastname: Torres
authors.forename: H M
authors.initials: HM
authors.lastname: Johnson
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism* / Q000494:pharmacology; D001667:Binding, Competitive; D005260:Female; D007371:Interferon-gamma / Q000096:biosynthesis*; D051379:Mice; D008810:Mice, Inbred C57BL; D011945:Receptors, Angiotensin / Q000032:analysis* / Q000502:physiology; D017483:Receptors, Vasopressin; D013329:Structure-Activity Relationship; D006377:T-Lymphocytes, Helper-Inducer / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D014667:Vasopressins / Q000494:pharmacology
chemical_list: D000276:Adjuvants, Immunologic; D011945:Receptors, Angiotensin; D017483:Receptors, Vasopressin; D014667:Vasopressins; D001127:Arginine Vasopressin; C009038:pressinoic acid; D007371:Interferon-gamma