(1) Reproduction method for 24 month old rats, detection of adrenal cortex 3 β- Hydroxysterol dehydrogenase (3 β- HSD, testicular enzymes.
(2) Model characteristics: Leydig cells in the testes of elderly animals 3 β- HSD and glucose-6-phosphate dehydrogenase (G-6-PD) content, adrenal cortex 3 β- The HSD content has significantly decreased.
(3) Comparative medical clinical research results show that elderly people and patients with kidney yang deficiency have similar abnormal feedback regulation abilities in endocrine axis (mainly thyroid and gonadal axis) and immune function, but the degree of dysfunction in kidney yang deficiency patients is more pronounced than in elderly people. Although elderly people may not necessarily have the appearance of kidney (yang) deficiency, they have the connotation of kidney (yang) deficiency syndrome, so they can be called physiological kidney deficiency. Based on this, people choose elderly animals as models for kidney (yang) deficiency syndrome. However, clinical research on the essence of aging has not fully supported the differentiation of kidney yang deficiency in this model: aging is not a disease, there are many factors involved in aging, and individual differences are also significant. Judging the degree of aging solely based on age or appearance is not comprehensive enough. In addition, the feedback patterns of the two are different. The feedback constraint relationship between the pituitary gland and the target gland in patients with kidney yang deficiency is at a low level of balance. Most patients with kidney yang deficiency lack compensatory response from the pituitary gland to the decline of target gland function, while the pituitary gland in elderly people still has a certain compensatory ability despite varying degrees of target gland dysfunction. Therefore, using elderly animals as models for kidney yang deficiency syndrome also requires dialectical screening.