Development of specific antisera against 9-desglycinamide-8-arginine vasopressin by site-specific immunization.

Four specific and sensitive antisera against 9-desglycinamide-8-arginine vasopressin (DGAVP) were obtained by means of site-specific immunization in rabbits, using a Keyhole Limpet haemocyanin-DGAVP conjugate synthesized by a specific reaction of a thiol function with a maleimide group. Compared with conventionally raised antisera, the cross-reactivity with endogenous arginine vasopressin (AVP) and vasopressin-derived fragments was substantially lower. Interassay variability was 18.1% at maximum. Possible applicability of the new antisera in pharmacokinetic studies of DGAVP with respect to blood-brain barrier transport was tested by means of a pilot study in the rat.