ROLE OF ENDOGENOUS CARDIAC-GLYCOSIDES IN THE SPONTANEOUSLY HYPERTENSIVE RAT - ANTAGONISM BY ACTIVE IMMUNIZATION

The effects of simultaneous active immunization against two cardiac gl ycoside drugs, digoxin and proscillaridin, have been examined in young spontaneously hypertensive and Wistar-Kyoto rats. Control animals wer e immunized with protein carrier only. Animals were studied from 5 wee ks to 13 weeks of age. Effectiveness of immunization to produce antibo dy responses was assessed at the end of the study by estimating the ti ter of antibodies in plasma against both of the antigens. Robust antib ody responses were obtained. Immunization had no effect on the normal growth of these animals. Further, immunization against cardiac glycosi des did not change blood pressure in either strain of animals. Blood p ressure in the SHR increased as anticipated as the weanling animals gr ew to maturity, These studies indicate that active immunization agains t cardiac glycosides does not alter blood pressure in the SHR in spite of strong evidence for increased levels of endogenous cardiac glycosi des in this strain.