**5.5.2 Noradrenaline**

Noradrenaline (NA) is a cathecolamine secreted by neurons in the adrenal medulla and by chromaffin cells present in the adrenal cortex. In luteal bovine cells NA stimulates progesterone secretion through the beta 1- and beta 2-adrenoceptors. NA also increases cytochrome P-450scc and 3 beta-HSD activity. Prostaglandin F (PGF) inhibits the luteotropic effect of NA on the luteal tissue (Miszkiel&, Kotwica, 2001).
