ABSTRACT
Training different animal groups of the female rat with the hormones: testosterone, oestradiol, hexoestrol, progesterone, hexoestrol [+] progesterone and cortisone, facilitated the uptake of HRP by the brain and spinal cord. The hormones were applied-dissolved in sesame oil-daily for four months. The doses daily injected [s.c.] were 40, 50 and 10 micro g/100 g body weight of testosterone, oestradiol and each other hormone respectively. HRP [14.137 mg/100 g .body weight] was injected [i.v.] one, two and six hours pre the assay. The uptake of HRP by the brain and spinal cord depended on B-BB dysfunction and/or the process of pinocytosis. In addition the quantity of HRP taken b/ the brain and spinal cord varied according to the applied hormone, the time of circulation of HRP and the investigated tissue