Effects of Suppression of Pituitary Gonadotrophins on Blood Pressure in the Fowl

Abstract

The blood pressure level of adult White Leghorn chickens is approximately 20% higher in males than in females. The capon has the same level as the male. Diethyl-stilbestrol given over a period of 30 days (45 mg) suppressed sexual development and the output of pituitary gonadotropins and depressed blood pressure significantly in males and capons but had no effect on females. Pregnant mare serum, (PMS) injected at 100 rat units (R U) daily for 9-11 days to males and females whose pressure were depressed with the estrogen, returned pressures to normal level. PMS had no effect on blood pressure of females. 2-amino, 5-nitrothiazole, also suppressed sexual development, and depressed blood pressure of males and capons.