Thyroid hormone stimulates renin synthesis in rats without involving the sympathetic nervous system. Kobori, Hiroyuki, Atsuhiro Ichihara, Hiromichi Suzuki, Yutaka Miyashita, Matsuhiko Hayashi, and Takao Saruta. Department of Internal Medicine, School of Medicine, Keio University, Tokyo, Japan
APStracts 3:0214E, 1996.
The present study was performed to examine whether renal expression of the renin gene is regulated by thyroid hormone. Thirty male Sprague -Dawley rats were divided into hypothyroid, control, and hyperthyroid groups using daily intraperitoneal administration of methimazole, saline vehicle, or thyroxin, respectively. Each group was further subdivided into sympathetic innervated and sympathetic denervated subgroups using intraperitoneal administration of saline vehicle or 6-hydroxydopamine. Plasma renin activity and renal levels of renin were measured by radioimmunoassays after 8 weeks. Renal expression of renin mRNA was evaluated by a semiquantitative reverse transcriptase -polymerase chain reaction. Compared with control animals, plasma renin activity, renal level of renin, and renal expression of renin mRNA were reduced (82%, 94%, and 71%, respectively) in hypothyroid animals and elevated (155%, 1182%, and 152%, respectively) in hyperthyroid animals. Sympathetic denervation had no independent effect on these renin values. Our results indicate that thyroid hormone stimulates renin synthesis without involving the sympathetic nervous system.

Received 24 May 1996; accepted in final form 27 September 1996.
APS Manuscript Number E457-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 13 November 1996