Rilmenidine Phosphate

Rilmenidine phosphate is the water soluble form of Rilmenidine. It is an antihypertensive drug targets the imidazoline receptor. [1]
Imidazoline receptor is a family of non-adrenergic high affinity binding site for clonidine, idazoxan, and other imidazoline drugs. [2] There are three types of imidazoline receptor. I-1 mediates sympatho-inhibitory actions to the lower blood pressure; I-2 is allosteric binding site of monamine oxidase and I-3 controls insulin secretion of pancreatic cells. [3]
In Hep G2 cells treated with 0.5 mM oleic acid for 6 hours and 1μm Rilmenidine for 30 minutes, the oleic acid-induced lipid accumulation decreases. [4] Stimulation of imidazoline I-1 receptor by Rilmenidine activated P38 to induce the expression of FXR. [4]
Mice fed with HFD (high fat diet) had improved hepatic steatosis following the administration of Rilmenidien through the activation of imidazoline I-1 receptor. [4] Imidazoline receptors are involved in the bulbospinal regulation of blood pressure and affect peripheral stimulation. [1] In hypertensive patients, Rilmenidine decreased blood pressure in a dose-dependent mater. In contrast with placebo, Rilmenidine had significantly lowered blood pressures. In addition, Rilmenidine had significantly less incidences of adverse effects than using other drugs for hypertension. [1]
References:
[1] Laurent S, Safar M. Rilmenidine: a novel approach to first-line treatment of hypertension. Am J Hypertens. 1992 Apr;5(4 Pt 2):99S-105S.
[2] Regunathan S, Reis DJ. Imidazoline receptors and their endogenous ligands.Annu Rev Pharmacol Toxicol. 1996;36:511-44.
[3] Head GA, Mayorov DN. Imidazoline receptors, novel agents and therapeutic potential. Cardiovasc Hematol Agents Med Chem. 2006 Jan;4(1):17-32.
[4] Yang PS, Wu HT, Chung HH, Chen CT, Chi CW, Yeh CH, Cheng JT. Rilmenidine improves hepatic steatosis through p38-dependent pathway to higher the expression of farnesoid X receptor. Naunyn Schmiedebergs Arch Pharmacol. 2012 Jan;385(1):51-6.