Comparison of the effects of prolactin modulation after ovariectomy on some immune parameters in a high mammary tumour strain of SHN mice and ICR, most popular and ‘normal’ mice

摘要

Beginning 15 days after ovariectomy (OVX) at 3 months of age, SHN and ICR mice received subcutaneous injections of danazol (D: 0.5 mg/0.1 ml olive oil, once a day), perphenazine (PER: 0.05 mg/0.05 ml saline, twice a day) or ovine prolactin (oPRL: 0.25 mg/0.05 ml buffer, twice a day) for 3 days to modulate circulating PRL levels. The weights of thymus and spleen were decreased by PER compared to OVX-control group in SHN but less decrease was seen in ICR. In both SHN and ICR, oPRL treatment increased immature thymocytes (CD4-+CD8-+) and decreased mature T cell subpopulations (CD4-+CD8-+ and CD4-+CD8-+), suggesting that oPRL may enhance release of mature T cells from the thymus to periphery. Treatment with PER or oPRL induced significant decreases in CD45R/B220-+ B cells in ICR, but in SHN, the number of CD45/B220-+ B cells was significantly increased by oPRL treatment. The effects of PRL modulation on some immune parameters in the oestrogen deficient conditions are not always conclusive in this study. However, the results strongly suggest that its effects are not intrinsically different between mouse models; SHHN, a high mammary tumour strain and ICR developing rarely the lesions.