Iganidipin is a new dihydropiridynic derivative of calcium antagonist. It is the only currently available calcium antagonist in the form of ophthalmic solution. Its topical administration increases ipsilateral optic nerve head blood flow in rabbits and monkeys and inhibits the contraction of blood vessels induced by endothelin -1. Iganidipin is also used for treat Angina pectoris and Hypertension.

Indolapril (CI-907) is a new orally active prodrug of nonsulfhydryl angiotensin-converting enzyme (ACE) inhibitor, developed by Warner-Lambert/Parke-Davis Pharmaceutical Research for treating hypertension. Indolapril is epimer of trandolapril, well-known ACE inhibitor currently in the market for hypertension treatment. Indolapril (Monoester form) and it’s active component (diacid form) produced concentration related ACE inhibition in guinea-pig serum (IC50 for monoester -- 0.1 mkM and for diacid -- 2.6 nM). In isolated rabbit aortic rings and in rat and dog autonomic studies, Indolapril is highly specific in suppressing the contractile or pressor responses to angiotensin I. In two-kidney, one-clip Goldblatt hypertensive rats, single daily doses (0.03-30 mg/kg p.o.) produced dose-dependent decreases in blood pressure; 3 mg/kg lowered blood pressure to normotensive levels. In the spontaneously hypertensive rat, subacute administration of Indolapril produced the same decrease in blood pressure as that obtained in the renal hypertensive rat. In diuretic-pretreated renal hypertensive dogs, 10 mg/kg normalized blood pressure. For equivalent drops in blood pressure, heart rate increases were less in Indolapril than in enalapril-treated renal hypertensive dogs. No side effects were observed with CI-907 in any of the conscious animals. The antihypertensive response to Indolapril (0.03-1.0 mg/kg p.o.) was found to correlate with inhibition of vascular tissue ACE, but not plasma or brain ACE in two-kidney, one-clip renal hypertensive rats.

Zolertine is an alpha-adrenergic receptor antagonist that acts as an antihypertensive agent. Its effect was studied in animals in vivo and in vitro. Zolertine considerably decreased systemic blood pressure in mecamylamine hypertensive dogs in a dose-related fashion. Using the intravital microscopic method in rat's mesocygeus microvasculature a direct relationship between zolertine dosage and blockade was demonstrated as well as an inverse relationship between time of action of zolertine and percentage of vasoconstriction caused by noradrenaline. When only zolertine was applied, it caused a small vasoconstriction that decreased as its concentration increased which could be due to its ability to antagonize alpha receptor responses, but not beta responses. Zolertine is a more active alpha blocker than azapetin, a blocker used in medical practice. Competition binding experiments using the alpha1-adrenoceptor antagonist [3H] prazosin showed a zolertine pKi of 6.81 +/- 0.02 in rat liver (alpha1B-adrenoceptors) and 6.35 +/- 0.04 in rabbit liver (alpha1A-adrenoceptors) membranes. Zolertine showed higher affinity for alpha1D-adrenoceptors compared to alpha1A-adrenoceptors, while it had an intermediate affinity for alpha1B-adrenoceptors. The ability of the alpha1-adrenoceptor antagonist zolertine to block alpha1D-adrenoceptor-mediated constriction in different vessels of Wistar Kyoto (WKY) and spontaneously hypertensive (SHR) rats may explain its antihypertensive efficacy despite its low order of potency.

Carmoxirole is a dopamine D2 receptor agonist with limited central activity that modulates sympathetic activation and subsequently reduces pre-load and afterload in animals. It was shown, that carmoxirole induced beneficial effects on hemodynamic and neurohumoral parameters in heart failure. In addition, experimental evidence showed that carmoxirole lowered blood pressure in various models of hypertension mainly or exclusively through inhibition of noradrenaline release from sympathetic nerve endings. That effect of carmoxirole was mediated by presynaptic dopamine receptors with the characteristic that release inhibition was restricted to low rates of sympathetic nerve discharge.

ICI-118551 is a selective β2 adrenergic receptor antagonist, that was originally developed for the regulation of blood pressure. ICI-118551 crosses the blood-brain barrier and it was in phase I clinical trials for the treatment of chronic anxiety. Currently, ICI-118,551 has no known therapeutic use in humans although it has been used widely in research to understand the action of the β2 adrenergic receptor, as few other specific antagonists for this receptor are known.

Indolapril (CI-907) is a new orally active prodrug of nonsulfhydryl angiotensin-converting enzyme (ACE) inhibitor, developed by Warner-Lambert/Parke-Davis Pharmaceutical Research for treating hypertension. Indolapril is epimer of trandolapril, well-known ACE inhibitor currently in the market for hypertension treatment. Indolapril (Monoester form) and it’s active component (diacid form) produced concentration related ACE inhibition in guinea-pig serum (IC50 for monoester -- 0.1 mkM and for diacid -- 2.6 nM). In isolated rabbit aortic rings and in rat and dog autonomic studies, Indolapril is highly specific in suppressing the contractile or pressor responses to angiotensin I. In two-kidney, one-clip Goldblatt hypertensive rats, single daily doses (0.03-30 mg/kg p.o.) produced dose-dependent decreases in blood pressure; 3 mg/kg lowered blood pressure to normotensive levels. In the spontaneously hypertensive rat, subacute administration of Indolapril produced the same decrease in blood pressure as that obtained in the renal hypertensive rat. In diuretic-pretreated renal hypertensive dogs, 10 mg/kg normalized blood pressure. For equivalent drops in blood pressure, heart rate increases were less in Indolapril than in enalapril-treated renal hypertensive dogs. No side effects were observed with CI-907 in any of the conscious animals. The antihypertensive response to Indolapril (0.03-1.0 mg/kg p.o.) was found to correlate with inhibition of vascular tissue ACE, but not plasma or brain ACE in two-kidney, one-clip renal hypertensive rats.

DL-Tetrahydropalmatine (dl-THP), an active component isolated from Corydalis species (a Chinese herbal medicine). dl-THP has inhibitory effects on liver injury induced by carbon tetrachloride in mice. The drug demonstrated anxiolytic and anti-nociceptive effects in animal models. dl-THP may act through inhibition of amygdaloid dopamine release to inhibit an epileptic attack – it is a very effective anti-epileptogenic and anticonvulsant agent. dl-THP has been found to have antihypertensive effects. It acts through the 5-HT2 and/or D2-receptor antagonism in the hypothalamus to induce hypotension and bradycardia in rats.

(S)-Alprenolol is a more active stereoisomer of antihypertensive beta-blocker alprenolol. Its activity against beta-adrenoreceptor is 100 times greater than the activity of (R)-alprenolol. In a model of ventricular arrhythmias produced by ligation of the left coronary artery, (S)-alprenolol was effective at 7.5 mg/kg, whereas (R)-alprenolol abolished the ventricular arrhythmia by cumulative dose of 15.5 mg/kg. As a most active enantiomer of alprenolol, the compound was used as a tool to study beta-adrenergic receptors.

LY-272015 is an antagonist at serotonin 5-HT2B receptor. LY-272015 exerts antihypertensive action in animal models.

Epipinoresinol is an important component of the medicinal herb Eucommia ulmoides, which has a substantial reputation as an effective antihypertensive remedy. Epipinoresinol (EPR) belongs to the group of furofuran-type lignans consisting of two phenylpropane units. (+)-epipinoresinol exhibited antiplatelet aggregation activity. It also exhibited inhibitory effects on nitric oxide production. Epipinoresinol possess antiproliferative activity.