|Budget Amount *help
¥2,300,000 (Direct Cost : ¥2,300,000)
Fiscal Year 1995 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1994 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1993 : ¥800,000 (Direct Cost : ¥800,000)
The final goal of our project is to clarify the role of the renal sympathetic nervous system in the pathogenesis of essential hypertension. At the first step, to clarify the distribution of the adrenergic receptor, we performed reverse transcription-polymerase chian reaction (RT-PCR) using total RNA extracted from each nephron segment microdissected from the rat kidney and localized the tubular distribution of mRNA expression of the angiotensinogen, adenosine A_1 receptor and alpha_<1B>-adrenergic receptor. The products of these RT-PCR were detected by ethidium bromide staining and Southern blott hybridization using specific probes for these genes.
Angiotensinogen mRNA was found in the proximal tubules and glomerulus. As well, we found the growth dependent decrease of these expression (In submission).
Adenosine A1-receptor mRNA was distributed at the glomerulus, medullary and cortical thick ascending loop of Henle, medullary and cortical collecting tubules and proximal tubules (Hypertension 26 : 1181-1185,1995). Finally, we have shown the distribution of alpha_<1B>-adrenergic receptor mRNA at the glomerulus, proximal tubules and medullary and cortical loop of Henle (Kidney Int.1997, in press).
In the near future, we will perform similar studies on the other adrenergic receptors such as alpha_<1A>-, alpha_<1D>-, alpha_<2A>-, alpha_<2B>-, alpha_<2C>-, and beta-adrenergic receptors. These results give us important basic informations to evaluate the roles of renal sympathetic nervous system in essential hypertension.