Effect of Neonatal Aromatase Inhibition on Neuron Number in the Superior Cervical Ganglion and Blood Pressure in the SHR Rat

The objective of this experiment was to examine the role of estrogen in the development of hypertension and the superior cervical ganglion (SCG) in the spontaneous hypertensive rat (SHR). SHR and normotensive Wistar‐Kyoto (WKY) male rats were treated daily with an aromatase inhibitor (Letrazol, Ciba‐Geigy) from birth to postnatal day 15 to determine the effect of blocking estrogen synthesis on adult neuron number and blood pressure. Blood pressure was measured at 84 days of age and ganglia were removed and prepared for cell counting. Males of both strains treated with Letrazol exhibited a significant decrease in blood pressure and neuron number compared to controls. Organ weight, body weight, ganglion volume, cell density and mean soma size were not affected in either strain. These data indicate that estrogen has a developmental effect on blood pressure and sympathetic cell number regardless of strain. This work was supported by a faculty grant from The University of Akron.