Immunological Depression in Spontaneously Hypertensive Rats

Abstract

The thymuses of young SHR rats before developing hypertension had reduced numbers of immature T-lymphocytes which were detected by the rosette formation test with guinea pig erythrocytes, whereas the thymuses of other eight rat strains tested contained about 60% rosetting cells. The number of rosetting cells progressively decreased with age. The blastogenic responses to PHA of the SHR rat lymphocytes was depressed to less than one fifth when compared to those of other rat strains including W/Mk rats, the original colony of the SHR rats. Other cell-mediated immune responses, including delayed hypersensitivity, allograft rejections, and a cooperation of T- and B-lymphocytes to produce humoral antibody formation were significantly depressed when compared to those of other rat strains.