ABSTRACT
The effect of cimetidine and ranitidine [as H[2] receptor antagonists] on serum prolactin and testosterone levels and testicular structure in albino rats were investigated. Thirty healthy male adult Albino rats were used, they were divided into three groups, ten animals each, a control group, and 2 experimental groups [cimetidine and ranitidine groups]. Long term administration of doses equivalent to human therapeutic dose range of both cimetidine and ranitidine were used. In cimetidine group, a dose of 8 mg/Rat was administered intraperitoneally daily for one month. It produced highly significant increase in serum prolactin level [P < 0.001] and also highly significant decrease in serum testosterone level [P < 0.001]. Microscopically the testis showed a decrease in size of the seminiferous tubules and reduction in germinal layers with arrest of spermatogenesis in level of spermatid. Neither Sertoli cells nor Leydig cells showed any significant changes as compared with the control group. In ranitidine group a dose of 3 mg/Rat was administered intraperitoneally daily for one month. This group showed normal serum prolactin and testosterone level, and normal microscopic structure of the testis as compared with the control group