Gonadotrophin continued

The recombinant production of FSH and LH also obviously facilitates the generation of a pure preparation of any one gonadotrophin, without contamination by a second gonadotrophin. Such preparations continue to facilitate a greater understanding of the precise role each gonadotrophin plays in reproductive function. 

Inhibition of ovulation presents a different and easier biological problem. There is no need to suppress continuous formation of the gametes, as in the male, but only to prevent their release from the ovary approximately 13 times a year. Either the pituitary gonadotrophin may be inhibited or the ovary may be made unresponsive to it. 

One of the earliest such POC tests developed was the home pregnancy test. It is based on a qualitative immunological antibody assay. It relies on the determination of human chorionic gonadotrophin (hCG) levels in urine, which gives rise to a coloured band if positive. The device is very small and completely disposable. A quality control check is built in where the rest of the urine sample continues along the dipstick and interacts with a pH-sensitive indicator to show that the test has been performed correctly. 

Our localization for the LRF and FRF is consistent with the findings that pituitaries grafted to this region retain gonadotrophs (34,35) and that gonadotrophin secretion can continue after isolation of the medial basal tuberal region from the rest of the CNS (36). 

It should be mentioned that sex differences in gonadotrophin activity (continuous in males and cyclical in females) are not associated with the hypophysis (which has an equal potential in both sexes), but are associated with the hypothalamus. It was found that the male pattern of gonadotrophin secretion is formed several days after delivery as a result of an effect of testicular hormones on nerve structures in the brain above the hypothalamus (Yazaki, 1960). Castration or neutralization of the sex hormones by reserpine injection (which eliminates testicular hormones from newborn males) affects hypothalamus action (Levina, 1974). 

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